And as you would that men should do to you, do you also to them likewise. For if you love them who love you, what thanks have you? for sinners also love those that love them. And if you do good to them who do good to you, what thanks have you? for sinners also do even the same. And if you lend to them of whom you hope to receive, what thanks have you? for sinners also lend to sinners, to receive as much again. But love your enemies, and do good, and lend, hoping for nothing in return; and your reward shall be great, and you shall be the children of the Highest: for he is kind unto the unthankful and to the evil. Be you therefore merciful, as your Father also is merciful.
(Luke 6:31-36)