In Mark 8:35 Jesus tells us,
“For whoever would save his life will lose it, but whoever loses his life for my sake and the gospel’s will save it.”
Yeah, it’s not supposed to make sense. That is not the way we think. That is not how it goes in this world. And that’s the whole point.
John Stott paraphrases what Jesus is saying:
If you insist on holding on to yourself and living for yourself and refusing to let yourself go, you will lose yourself. But if you are prepared to lose yourself, to give yourself away in love for God and your fellow human beings, then in that moment of complete abandon, when you think you have lost everything, the miracle takes place and you find yourself. (Why I Am a Christian, 93)