It may seem obvious that you should try to lift up your friends, but are you LIVING it every day?
Are you sometimes being a crypto-crab because you can't stand the ego blow of your friends rising up in life?
Are you 100% always cheering your friends on to achieve more? Are you actively helping them find opportunities? Are you being ever-vigilant in pointing out their follies and mistakes? Would you never for a second entertain the thought of letting your friends stagnate at a comfortable level?
Selfishness is often a good motivator in life, so what is a selfish reason to help your friends?
Remember the old adage that you are the average of your 5 closest friends?