Whether it is necessary for salvation that we should show our enemies the signs and effects of love?

Objections

Objection 1 : It would seem that charity demands of a man to show his enemy the signs or effects of love. For it is written (1 Jn. 3:18): "Let us not love in word nor in tongue, but in deed and in truth." Now a man loves in deed by showing the one he loves signs and effects of love. Therefore charity requires that a man show his enemies such signs and effects of love.
Objection 2 : Further, Our Lord said in the same breath (Mt. 5:44): "Love your enemies," and, "Do good to them that hate you." Now charity demands that we love our enemies. Therefore it demands also that we should "do good to them."
Objection 3 : Further, not only God but also our neighbor is the object of charity. Now Gregory says in a homily for Pentecost (In Evang. xxx), that "love of God cannot be idle for wherever it is it does great things, and if it ceases to work, it is no longer love." Hence charity towards our neighbor cannot be without producing works. But charity requires us to love our neighbor without exception, though he be an enemy. Therefore charity requires us to show the signs and effects of love towards our enemies.