Most relationships today, romantic and otherwise, run on something close to a contract, even if nobody calls it that. I'll do this if you do that. As long as this keeps working for both of us. The moment the deal stops feeling worth it, either side can reasonably walk. That framework works fine for a lot of things. It's a genuinely different framework than what marriage, in its oldest sense, was ever meant to be.
The difference in plain terms
A contract is conditional. Both parties agree to specific terms, and the agreement holds as long as both sides keep their end of it. Break the terms, and the other party is released. A covenant is a promise made regardless of the other person's performance. It doesn't dissolve the moment things get uneven, because it was never conditioned on things staying even in the first place.
Where this shows up in the Bible
The marriage language throughout Scripture consistently uses covenant terms, and it's frequently compared to God's own covenant with His people, a relationship that, according to the text, held even when the people were repeatedly unfaithful. That's an uncomfortable comparison if you're looking for an easy metaphor. It's also the point: covenant love isn't love that depends on the other person earning it moment to moment. It's a commitment that outlasts a bad season.
Why this actually matters, practically
Contract thinking asks, every time things get hard, "is this still worth it to me." Covenant thinking asks a different question: "we made a promise, so what does keeping it require of me right now." That second question doesn't disappear when your spouse is difficult to love for a while, which every spouse is, in every marriage, at some point. It's precisely in those seasons that the difference between the two frameworks matters most, because a contract gives you permission to leave right when a covenant is asking you to stay and do the harder work of repair.
This is not a defense of staying in danger
Covenant language is sometimes misused to keep people in relationships that are genuinely abusive, and that misuse is a serious distortion of what covenant actually means. A covenant asks for faithfulness and sacrificial love, not the endurance of harm. If your safety is at risk, that is a different situation, and one where getting help immediately is the right and responsible choice, not a failure of commitment.
For everyone else, in the ordinary hard seasons
Most marriages don't fail because of one catastrophic event. They erode slowly, through a thousand small moments where contract thinking quietly won out over covenant thinking, where "is this still worth it" replaced "what does keeping this promise ask of me." Choosing covenant, on purpose, especially in an unremarkable hard season nobody else can see, is what actually gets a marriage to the other side of it.
Written by Matt Perry, wedding officiant and Lead Pastor of Love Church San Diego.