8. He who does not love has not become acquainted with God [does not and never did know Him], for God is love.
9. In this the love of God was made manifest (displayed) where we are concerned: in that God sent His Son, the only begotten or unique [Son], into the world so that we might live through Him.
10. In this is love: not that we loved God, but that He loved us and sent His Son to be the propitiation (the atoning sacrifice) for our sins.
11. Beloved, if God loved us so [very much], we also ought to love one another.
12. No man has at any time [yet] seen God. But if we love one another, God abides (lives and remains) in us and His love (that love which is essentially His) is brought to completion (to its full maturity, runs its full course, is perfected) in us!
13. By this we come to know (perceive, recognize, and understand) that we abide (live and remain) in Him and He in us: because He has given (imparted) to us of His [Holy] Spirit.