Beloved, I am writing you no new commandment, but an old commandment that you had from the beginning. The old commandment is the word that you have heard.
John reminds you that he teaches nothing new about love; it is what the faithful heard from the beginning and have long known. His point is not that love was prescribed ages before, but that you were taught it upon entering the faith itself, straight from Christ, so you have no reason to reject it as strange doctrine.
AI summary
The precept of love is old, yes, but it admits new enforcements and motives suited to each age. In innocence men would love as one blood; in sin and recovery, as partners in hope; in the covenant people, as heirs of the Messiah; and now in the gospel church, with obligations renewed by Christ Himself.
AI summary
Commenting on 1 John 2:7-11
This commandment of love is ancient because it flows from God's eternal nature, He is love itself, and was written on Adam's heart, delivered in Moses' law, taught by Christ from the gospel's beginning, and imparted to you at your conversion, so it deserves respect as doctrine of the greatest antiquity, not some upstart notion.
AI summary