I cannot speak for all Christians since you get down to single-person branches, but for Catholicism it's quite an interesting evolution of usury.

You begin with the Bible laying it out as a sin (keep in mind that it's not like the Bible is left behind by Jesus, it took a couple of centuries for it to get settled.

By the 300s, they had very much forbidden clergy from engaging in usury. It was generally considered a bad thing.

In the Third Lateran Council (~1100s), they had forbidden it of all Catholics, banning any notorious usurer from receiving Communion or a Catholic Burial.

The Council of Vienne 200 years later then went even further, adding that they condemned any secular legislation engaging in usury.

Then in the 1500s, you get the Fifth Lateran Council and the big change is that they actually define usury:

> the real meaning of usury: when, from its use, a thing which produces nothing is applied to the acquiring of gain and profit without any work, any expense or any risk.

That same council outright allowed collecting interest for the specific purpose of Mount of Piety (think of it as a credit union and a not for profit mixed together). Since I've seen a lot of Jewish involvement in banking, these institutions were intended to be competition for Jewish bankers who were considered to be charging excessive fees for their services.