In the last of the six antitheses, Matthew focuses on the love command. . While there is no command to hate the enemy in the Old Testament, yet, there are statements that God hates all evildoers and statements that imply that others do or should do the same. Jesus, makes explicit here the command to love enemies. The conduct of the disciples of Jesus must reveal who they are really are, namely “sons and daughters of God”.
The command to “be perfect as your heavenly Father is perfect” does not mean to be without faults, but means to be undivided in love as God is undivided in love.
The love we have for others is more often than not a conditional love. We indulge in barter exchange and term it love. We are willing to do something for someone and expect that they do the same or something else in return. It is a matter of “give”, but also a matter of “take”. When Jesus asks us to be like the heavenly Father, he is calling us to unconditional love.