If anyone says, “I love God,” but hates his brother, he is a liar. For anyone who does not love his brother, whom he has seen, cannot love God, whom he has not seen. And we have this commandment from Him: Whoever loves God must love his brother as well.
By this the children of God are distinguished from the children of the devil: Anyone who does not practice righteousness is not of God, nor is anyone who does not love his brother. This is the message you have heard from the beginning: We should love one another. Do not be like Cain, who belonged to the evil one and murdered his brother. And why did Cain slay him? Because his own deeds were evil, while those of his brother were righteous. So do not be surprised, brothers, if the world hates you. We know that we have passed from death to life, because we love our brothers. The one who does not love remains in death. Everyone who hates his brother is a murderer, and you know that eternal life does not reside in a murderer. By this we know what love is: Jesus laid down His life for us, and we ought to lay down our lives for our brothers. If anyone with earthly possessions sees his brother in need, but withholds his compassion from him, how can the love of God abide in him? Little children, let us love not in word and speech, but in action and truth. And by this we will know that we belong to the truth, and will assure our hearts in His presence: Even if our hearts condemn us, God is greater than our hearts, and He knows all things. Beloved, if our hearts do not condemn us, we have confidence before God, and we will receive from Him whatever we ask, because we keep His commandments and do what is pleasing in His sight. And this is His commandment: that we should believe in the name of His Son, Jesus Christ, and we should love one another just as He commanded us.
The LORD your God will circumcise your hearts and the hearts of your descendants, and you will love Him with all your heart and with all your soul, so that you may live.
Now about brotherly love, you do not need anyone to write to you, because you yourselves have been taught by God to love one another. And you are indeed showing this love to all the brothers throughout Macedonia. But we urge you, brothers, to excel more and more
Since you have purified your souls by obedience to the truth so that you have a genuine love for your brothers, love one another deeply, from a pure heart.
For God, who said, “Let light shine out of darkness,” made His light shine in our hearts to give us the light of the knowledge of the glory of God in the face of Jesus Christ.
But now that you know God, or rather are known by God, how is it that you are turning back to those weak and worthless principles? Do you wish to be enslaved by them all over again?