Beloved, let us love one another: for love is of God; and every one that loveth is born of God, and knoweth God. – 1 John 4:7

True knowledge is essential to salvation. God does not save us in the dark. He is our “light and our salvation.” We are renewed in knowledge after the image of Him that created us. Now, “he that loveth not knoweth not God, for God is love.” All you have ever been taught from the pulpit, all you have ever studied from the Scriptures, all you have ever gathered from the learned, all you have collected from the libraries, all this is no knowledge of God at all unless you love God; for in true religion, to love and to know God are synonymous terms. Without love you remain in ignorance still, ignorance of the most unhappy and ruinous kind.

“Beloved, if God so loved us, we ought also to love one another. If we love one another, God dwelleth in us, and His love is perfected in us.” Now no man is a Christian who does not love Christians. He, who, being in the church, and yet not of it with heart and soul, is but an intruder in the family. But since love to our brethren springs out of love to our one common Father, it is plain that we must have love to that Father, or else we shall fail in one of the indispensable marks of the children of God. “We know that we have passed from death unto life, because we love the brethren;” but we cannot truly love the brethren unless we love the Father; therefore, lacking love to God, we lack love to the church, which is an essential mark of grace…Oh! Christian, thou canst not have the nature of God implanted within thee by regeneration, it cannot reveal itself in love to the brotherhood, it cannot blossom with the fair flowers of peace and joy, except thine affection be set upon God. Let Him then be thine exceeding joy. Delight thyself also in the Lord. O love the Lord ye His saints. ~ C.H. Spurgeon

https://www.blueletterbible.org/Comm/spurgeon_charles/sermons/1008.cfm