Not a Christian, but I spend a lot of time at church (long story). Anyway, self-sacrifice is one of the central tenets of Christianity, the idea being that Jesus Christ took on human form to suffer and die on the cross to save humanity from its grievous sins. As a result, self-sacrifice and martyrdom come up all the time in the Bible [1].
I'm not particularly good at actual theology, and I'm sure different sects of Christianity have different interpretations, but as I understand it, because of Christ's sacrifice, personal suffering is seen as something noble, or even venerable. I think it's easy to take this too far (e.g. people not accepting help because it's "noble" to suffer, or that they "deserve it"), but I digress.
From my personal experience, you are going to have misery no matter what in life. But it's amazing how often times some misery is bimodal, either you choose your misery, or it's forced on you.
As an example, you work and get paid (a form of misery because you don't have control over your own time), or you don't work and have all the time you want in the day (the misery is you are hungry cold and wet).
I found that self sacrifice in relationships almost always pays off, and is very biblically based concept. For example, being patient with a spouse you are angry with actually hurts emotionally (chosen misery), but you resolve things this way. The opposite would be to blame or fight back, and extend or lose control of the misery (ie, forced on you).
I've learned to chose my misery. Save now (misery chosen), spend now (misery forced later), etc... Maybe suffering would work equally well with misery.
I'm not particularly good at actual theology, and I'm sure different sects of Christianity have different interpretations, but as I understand it, because of Christ's sacrifice, personal suffering is seen as something noble, or even venerable. I think it's easy to take this too far (e.g. people not accepting help because it's "noble" to suffer, or that they "deserve it"), but I digress.
[1] https://bible.knowing-jesus.com/topics/Self-Sacrifice