The medieval church pictured love as a four-petaled flower on a single stem: love of God, love of self, love of neighbor, love of enemy. The same sap runs through every petal. Doriani notes that Jesus’ radical command in verse 44 is not a new petal grafted onto a different plant; it is the natural extension of the same love that began with the Father. If you love God truly, that love overflows into a sober love of self as one made in his image, and then into the love of neighbor, and then, on the same stem, all the way to the enemy.
Notice that Jesus does not merely forbid hatred; he commands action. Love your enemies. Pray for those who persecute you. Chrysostom said that he who prays for himself performs an act of nature, but he who prays for his enemy performs an act of grace. Praying for yourself is normal; praying for your persecutor is supernatural. Blomberg points out that the proof of regeneration is precisely here, where natural love runs out. Anyone can love the easy people; even the tax collectors do that.
One pastor said you cannot genuinely pray for someone without hoping good for them. Test it. Try praying by name for the person you most resent. Do it daily. You will discover that prayer changes you long before it changes them. That, in fact, is the goal. The aim of praying for your enemy is not first their conversion but yours. If a flower is missing a petal, it is not a different flower. It is a damaged flower. Jesus wants to restore the whole bloom.