“For one human being to love another human being: that is perhaps the most difficult task that has been given to us, the ultimate, the final problem and proof, the work for which all other work is merely preparation.”

“Love is difficult. For one human being to love another human being, that's the most difficult test that has been entrusted to us. The work for which all other work is merely preparation.”

“To love is good, too: love being difficult. For one human being to love another: that is perhaps the most difficult of all our tasks, the ultimate, the last test and proof, the work for which all other work is but preparation...Love is a high inducement to the individual to ripen, to become something in himself, to become world for himself for another's sake, it is a great exacting claim upon him, something that chooses him out and calls him to vast things.”

“Human beings owe a debt of love to one another because there is no other method of paying the debt of love and care which all of us owe to providence.”

“The overall purpose of human communication is - or should be - reconciliation. It should ultimately serve to lower or remove the walls of misunderstanding which unduly separate us human beings, one from another.”

“To try to understand another human being, to grapple for his ultimate depths, that is the most dangerous of human endeavors.”