Bible Verses About Self-Denial: Danger of neglecting

For whosoever would save his life shall lose it: and whosoever shall lose his life for my sake shall find it.

For what shall a man be profited, if he shall gain the whole world, and forfeit his life? or what shall a man give in exchange for his life?

but I buffet my body, and bring it into bondage: lest by any means, after that I have preached to others, I myself should be rejected.