John makes a very bold observation from both a spiritual and behavioral standpoint; Everyone who truly loves has been born of God and knows God. The only reason why we can love is supernatural because God's spirit resides within us. Without that spirit, we cannot do it on our own. When you walk with God humbly, you will not steal from people, cheat them, deal unreasonably against them, and be evil towards them. If you love God, you can love people because you will be equipped to pay the love shown towards you, forward.