This is a fantastic question recently raised - and one I'm surprised hasn't been brought up in any substance before. Let's look at what the Bible says and follow that up with some common sense that our modern culture has over-thunk itself out of.

BIBLICAL PRECEDENT

Everyone should have 2 Cor. 6:14 memorized by now, it's quoted so often here: "Do not be yoked together with unbelievers." But have you kept reading? *"For what do righteousness and wickedness have in common? Or what fellowship can light have with darkness? What harmony is there between Christ and Belial? Or what does a believer have in common with an unbeliever? What agreement is there between the temple of God and idols?" In short, when it comes to saved v. unsaved, the two are *so drastically incompatible that compatibility actually matters.

Okay, beyond salvation, how important does God view the issue of compatibility? Let's start with the history of marriage throughout Scripture and see where we go.

First, there's Adam and Eve. God creates Eve to be his helper. Eve is created in Eden to be a suitable helper for Adam. The imperative here is that any "compatibility" is for the designed purpose of fulfillment of the mission for which she was to help - not that they shared common interests. There wouldn't even have been any interests on the first day of creation to know to vet for in the first place. Moving on.

After that, the next story of substance we have of biblical couples finding marriage is Isaac and Rebekah. Abraham orders his servant to find a wife for Isaac in another town so Isaac doesn't have to marry one of the local Canaanites. He asked God that she at least be someone who would give a drink to a stranger and his camels. The first girl who came along (Rebekah) did just that. Was compatibility at issue here? The only "compatibility" requirement was that she not be a Canaanite - and even Isaac didn't have a say in that aspect, as that command came from Abraham.

The next one is Jacob, who fell in love with Rachel because of her beauty. He got a bad case of ONEitis. He had to marry Leah first, then he got to marry Rachel, then eventually each of their servants. There's no mention of actual compatibility with Rachel, other than the assumption that they stopped sleeping together (and that even before he married their servants). This is evident from her demand that Jacob "Give me children, or I'll die!" As in, "Why won't you sleep with me anymore?!?" Of course, Jacob gets angry with her because he really didn't want to and didn't believe it would help, so she says, "Fine, sleep with my servant instead." Yeah, this sounds like they were real compatible. He also was obviously not all that thrilled about marrying Leah either. By the time the servants came into the picture, I imagine Jacob was really just interested in having more women under his sheets, so he went along with it. Sure enough, despite the obviously tense situation in the whole household, God blesses the situation and gives Jacob 12 children who became the 12 named forefathers of the tribes of Israel. Compatibility didn't seem to be necessary for the fulfillment of God's blessings here.

Somewhere along the way comes Ruth and Boaz. He basically sees her out in the field and finds her attractive. She sees a good man who can provide for her and sleeps with him (presumably non-sexually). There's no mention of shared interests here, other than that he liked growing things and she liked taking from what other people were growing.

Then comes David. Michal seems to think he's a great catch, even though he was poor and couldn't pay a bride price. Instead of money, Saul asks for 100 Philistine foreskins, and David was interested in Michal enough that he got Saul 200 instead, presumably to prove his desire for Michal. One could assume they thought each other a compatible match (though that's stretching it), but it ultimately doesn't matter, as their marriage ends very poorly, with the presumption that David stopped sleeping with her to focus on other women. Cue Bathsheba - the girl David hooked up with before murdering her husband to hide their adultery. This was a marriage of lust. While God condemned the act, he also blessed the marriage and had Solomon be born from her.

After him is Solomon. While he does share a lot of general wisdom, he also had hundreds of wives and concubines. It's hard to say if any of his marriages were particularly successful. At best, we can suggest that the lustful attraction to his beloved in Song of Solomon is honored. Yet again, there is little reference to compatibility.

There are also laws on the books that if a guy raped a woman or (with mutual consent) took her virginity, he was legally obligated to offer to marry her, at which point her father would decide if the marriage would go through. This would seem to be the opposite of compatibility, yet it's God's law to the Israelites all the same.

Generally, there's enough information throughout the books of the law to figure out that most of Israelite culture involved arranged marriages for familial convenience, not out of love or dating to assess compatibility between the bride and groom. At best, we could say that the only actual "compatibility" requirement was that

While marriages are referenced in the New Testament, there's no information that any of them - Joseph/Mary, the wedding where Jesus turned water to wine, etc. - were based on compatibility, arranged marriage, etc.

Jesus and Paul both encourage people who can avoid marriage to do so (Matthew 19; 1 Cor. 7). Paul elaborates on this that the only time he actually encourages marriage is if the two can't keep their hands off each other and they'd "burn" if they don't get married (I've always found humorous u/BluePillProfessor's note of the possible double-entendre here, as the "with passion" part is an editorial addition). Paul didn't say to look for someone compatible to marry; he said to avoid looking for someone to marry, but if you're so horny toward each other, that's the best time to start thinking of marriage.

Conclusion: Other than the requirement that both people be of God's Kingdom, compatibility is never referenced as a thing to look for in a potential spouse or successful marriage. In fact, it's curiously absent in a number of marriages that God seemed to bless anyway.

COMMON SENSE

Define Compatibility

You can't. You can give dictionary definitions, but what it means in a pragmatic sense is left wide open. Let's look at the dictionary definition:

  • "A state in which two things are able to exist or occur together without problems or conflict."

Sure, if you want to define "compatible" this way, then compatibility would be a useful asset in a marriage - though not necessarily to perfection. A little conflict is good. It breeds emotion, which keeps passion alive. Compatibility, in itself, is often boring. But let's look to the more practical consideration: How can you ever know if you're compatible with someone under this definition? You can't ... at least not until years after you're married. Because you can't know if you'll co-exist "without problems or conflict" until you actually co-exist (unless you move in together before marriage, which is best left for another day).

Moving on from the dictionary definition, the common use of the word is even less useful. People say they're compatible if they have the same shared interests. Others think it means that you have personalities that, while different, blend well together. Others mean you have the same core values and aspirations in life. So, how important is compatibility? I can't even answer the question until I know which you're talking about. But even then, the answer is most likely going to be simple: It's as important as you want to make it. Personally, I don't think it's important at all. Why not?

Back to the Bible

For a brief interlude, let's look back at Genesis. God creates Eve out of Adam to be a helper for him. That is, God designs Adam for a God-given purpose; and then he designs Eve for an Adam-given purpose ... which, of course, is her God-given purpose, vicariously and directly - (1) vicariously in that God gave Adam his purpose that she's to help on; and (2) God also directly gave her the purpose of helping her husband. Long story short, a successful marriage is defined not by the levels of the happiness of the couple, but by their utility toward the purposes for which God united them in marriage (which is to make disciples - Malachi 2:15, etc.). Because of this, God designed women to mold to their man's purposes. This is why we often see that many women (yes, I'm over-generalizing in modern culture) tend to struggle to have hobbies of their own, but quickly adopt the hobbies of their husbands, either as direct participants or as sidelined cheerleaders. It's why literal cheerleaders exist in the first place, for that matter ... at least until some feminist somewhere decided it needed to be about female empowerment and competition rather than supporting their men on the field, or even their community pride.

The point is: if God designed women with an innate desire to mold their life direction and interests to the men they find most attractive (which is one of their tools for keeping an attractive guy around), then it doesn't really matter whether you have:

  • ... shared interests, because those interests will conform to the man they want to be with. That's not to say women won't maintain independent interests. They will. But, on the whole, they are excited to adopt their man's interests also, if they find the man attractive and they want to be with him. The only broad-scope reason a woman wouldn't want to engage in her man's interests with him is if her attraction level toward him is lower than her interest in the activity he wants to do. Either he's unattractive, and therefore she's not motivated to do much of anything wit him; or he's attractive, but the activity is so repugnant to her that she's still not interested ... though Deep's Brad Pitt post shows that even this is still all part of sliding scale and would be flexible if he was hyper-attractive.

  • ... well-balanced personality traits, because as someone designed to be a helper, God created her to be able to fill in the gaps where her husband needs them. No, this isn't executed naturally in every marriage. But it is played out wonderfully in every biblical marriage. I have yet to meet a godly couple where the wife would not be gleeful to share all the ways that she helps cover the things that her husband doesn't have time, attention, or awareness to address - and a man who isn't ultimately glad that she does this.

  • ... core values and aspirations in life, because the wife's God-given purpose is to pursue the mission God gave him, therefore becoming God's mission for her. To say she wants to pursue her own values and aspirations separate from the ones he discerns from God to set for the marriage is to suggest that she knows better for her life than God knows for her. This, of course, is more difficult when you have someone whose values and aspirations are not coming from God - but even 1 Peter 3 says she should submit to such a man's leadership (which I've already written on before, and wont' do so again here).

People Change

Of course, the real common sense reason for ignoring "compatibility" is that people change. You can't ever predict what someone will be like in 10 years in the absence of you molding them during those 10 years. And if you're the one molding them, then who they are today is a lot less significant than who you're going to help them become tomorrow. This is, after all, the essence of discipleship and why Jesus was willing to die, even while he knew we were still sinners (Romans 5:8). Can you imagine if Jesus used "compatibility" as a standard before making us any part of his bride? - other than that Jesus was of the faith of Abraham, and therefore of "spiritual Israel" just as the Church also is (per Romans 9), and therefore the ONE area of necessary compatibility is satisfied.

I love my brother's comment shortly after he got engaged: "I wish I knew in high school how unimportant liking the same music was in a relationship." He literally only dated girls who liked the same bands as him. Idiot. My wife also once commented that when she was a kid she thought, "How are my aunt and uncle ever going to be happy in marriage? One is a [sports team 1] fan and the other is a [team 2] fan! How did they ever get married?"

See how juvenile those thoughts are? Yet the world still thinks this is true - that if you don't like the same things it will never work. It's laughable.

Working the Change

As a brief note, make sure you're actually giving her something to change into. Women WILL change no matter what you do. Period. It's a fact of life. Some basic aspects of their character may stay the same, but at the end of the day, they all have Next-Thing-itis, and that "Next-Thing" is what will keep them changing and always evolving. This isn't a bad thing - it can often even be a good thing! But it's a consistent thing, nonetheless.

With that in mind, if you're already "compatible" in the sense of being perfectly aligned with each other, there are only two ways this can go:

  1. She's going to change away to be less compatible with you, or

  2. You're going to keep changing to give her something to keep changing toward as well.

In the first instance - the one where you're not going to change, as a man - you're better off finding someone you're NOT compatible with, as that will at least buy you some time with the chance that her inevitable changing will eventually mold to who you are today. But this is only postponing the inevitable, even for the most attractive men.

In the second instance - the one where you're constantly changing as a man - you're either (1) changing for the worse and she's going to want to deviate away anyway ... because who wants to mold into the likeness of a rapidly deteriorating person? or (2) you're constantly improving yourself and giving her something to try to improve toward as well.

Which option do you prefer?

Two notes:

  • First, obviously this is ultimately a post about discipleship. Disciple your wife! Single guys, be prepared to disciple the girl who catches your eye! Stop looking for a "perfectly compatible unicorn" and expect to have to disciple her.

  • Second, also obviously: just because you shouldn't look for/expect compatibility doesn't mean you can ignore red flags. Having standards is necessary and appropriate.

Edit to Add: My wife and I are about the most incompatible couple I'm aware of. I've shared my story before about how she admitted years into our marriage that she lied about many facets of her personality and interests in order to get me to marry her, making us far less compatible than I had thought. I also started studying M-B typology late into our marriage and discovered that an ENTP (me) married to an ISFJ (her) not only has no personality trait in common - many message boards were saying (including from licensed marriage counselors) it was the worst possible combination for marriage in existence, often suggesting people to divorce and run away before you get too far down the rabbit hole to turn back. I believed these things would be problems and challenges for us for a long time - and, in fact, they were (when I wasn't focusing on taking care of myself and working my mission). Once I got myself pointed in the right direction:

  • My wife, while being a 98% I is actually the one who coordinates play dates with other moms, invites people over for dinner, connects people in the neighborhood, etc. - all very E traits.

  • While being a 58% S, instead of focusing on the details all the time, she's learned to look for patterns and threads between concepts, keep an eye out for the bigger picture, and plan events and activities from a bird's eye view rather than getting muddled down into the details too early - all very N traits.

  • While being a 92% F, she now opens difficult conversations with rational arguments rather than emotional whining and complaining, and when she finds herself getting flustered throughout the day she can stop and remind herself of good things that are going on in life as well to direct her feelings through rational thought rather than the other way around - very T traits.

  • As a 76% J, she still loves being organized and planning things in detail before getting started, or following the recipe exactly when cooking; yet she also recognizes that she EVEN MORE loves it when I throw all her planning out the window and spontaneously come up with better, more fun things to do or ways of doing things she had already planned to do - a bold embrace of the P.

No, M-B typology is not the focus here. My focus is that even a woman's core personality traits will ultimately mold to her man's - if not to adopt them completely herself, then at least to appreciate them and embrace them as her way of doing things too. To everyone who says an ENTP and ISFJ are incompatible and should never be married - now I just laugh because why did I ever think blue pill marriage counselors would ever have good advice in the first place?