There is no fear in love, but perfect love casts out fear. For fear has to do with punishment, and whoever fears has not been perfected in love. We love because he first loved us.

-1 John 4:18-19

“But the duty of love cannot be extorted and forced by fear, but it must be won, and sweetly allured  by an apprehension of God’s love and goodness towards us, as that eminent, loving and beloved disciple  testifies…

Observe here that we cannot be beforehand with God in loving Him, before we apprehend His love to us.  And consult your own experience, if you have any true love to God, whether it were not wrought in you  by a sense of God’s love first towards you? All the goodness and excellency of God cannot render Him an amiable object to us, except we apprehend Him an agreeable good to us.

The greater God’s excellency and perfection is, the greater evil He is to us, if He hates and curses us. And therefore the principle of self-preservation, deeply rooted in our natures, hinders us from loving that which we  apprehend as our destruction. If a man is an enemy to us, we can love him for the sake of our loving reconciled God, because His love will make man’s hatred to work for our good, but if God Himself is our enemy, for whose sake can we love Him? Who is there that can free us from the evil of His enmity and turn it to our advantage, until He is pleased to reconcile Himself to us?”

-Walter Marshall, The Gospel Mystery of Sanctification, p. 15-16