What does John 12:25 mean? What does this verse mean? Is this the reason why many good people die and lots of bad person are living the greed and wealth in this world? This keeps on bugging me.


  John 12:25
  
  ”Whoever loves his life loses it, and whoever hates his life in this
  world will keep it for eternal life.”
Generally this verse is understood as a poetic way of telling us what our priorities should be.  If we're focused on our temporary earthly life, we'll throw away our eternal life, but f we love the things of God and are willing to focus, instead, on things of eternal import, we will gain eternal life.


  Gill's Exposition of the Entire Bible
  
  He that loveth his life shall lose it,.... The sense is, that whoever
  is so in love with this present temporal life, as to be anxiously
  careful of it, and takes all precautions to secure it; and rather than
  to expose it to any danger, chooses to deny the faith of Christ, and
  desert his cause and interest; as such an one shall not long enjoy
  this life, so he shall come short of an eternal one:
  
  and he that hateth his life in this world: on the other hand, whoever
  seems careless about it, and not to consult the safety of it, but is
  unconcerned about it; yea, as if he was throwing it away, as of no
  great moment and significancy, rather than do anything to preserve it,
  which would be scandalous to himself, and be dishonourable to his Lord
  and master; he
  
  shall keep it unto life eternal: he shall be preserved in his temporal
  life, in a remarkable manner, until he has done the will and work of
  God, notwithstanding all attempts upon it; and he shall appear to have
  that spiritual life, which is the beginning and pledge of, and which
  springs up unto, and issues in eternal life; and that he shall enjoy
  in the world to come. This Christ said to let his disciples and
  followers know, that they must suffer and die, as well as he, though
  not on the same account, and for the self-same reasons; and that their
  sufferings and death in his cause, and for his Gospel, would turn to
  their advantage.


Similarly, from Grace in Focus


  Love and Hate Are Figures of Speech Concerning Priorities
  
  The person who “loves his life [psyche]” is one who is living for the
  now. He is contradicting Jesus’ command, “Don’t lay up treasure on
  earth” (Matt 6:19). He is failing to serve Jesus (“If anyone serves
  Me, him My Father will honor,” (John 12:26).
  
  The person who “hates his life [psyche]” is one who is living for the
  life to come. He is obeying Jesus’ command, “Lay up treasure in
  heaven” (Matt 6:20). He is following Jesus and serving Him and will
  one day be honored by God (John 12:26).