Jesus, completely and forever selfless, was adamantly intolerant of selfishness.
Selfish people make decisions based on their own needs and desires. Selfish people care only for themselves. Personal pleasures or advantage motivate and influence their decisions.
Selfishness is diametrically opposed to what Jesus and the Bible teach us about our relationships with others. A rich young ruler said he wanted to become a follower of Jesus. Jesus told him, “If you want to give it all you’ve got,” Jesus replied, “go sell your possessions; give everything to the poor. All your wealth will then be in heaven. Then come follow me. When the young man heard this he went away sorrowful, for he had great possessions.Matthew 19:21-22 The Message
We know from the Bible story the young ruler selfishly decided his worldly possessions were more important than the sacrifice Jesus asked him to make. Jesus taught, “For whoever wants to save their life will lose it, but whoever loses their life for me will find it.” (Matthew 16:25).
Paul taught us in Philippians,
Do nothing out of selfish ambition or vain conceit. Rather, in humility value others above yourselves, 4 not looking to your own interests but each of you to the interests of the others. Philippians 2:3-4.
Selfishness not only has life-altering consequences. Selfishness has health consequences as well. Self-pity and self-consciousness can contribute to hypochondria as well as depression and other stress-related illnesses.