Jamieson, Fausset and Brown on 1 John 2:24

24. Let that--truth respecting the Father and the Son, regarded as a seed not merely dropped in, but having taken root (1Jo 3:9).

ye--in the Greek standing emphatically at the beginning of the sentence. YE, therefore, acknowledge the Son, and so shall ye have the Father also (1Jo 2:23).

from the beginning--from the time of your first hearing the Gospel.

remain--Translate as before, "abide."

ye also--in your turn, as distinguished from "that which ye have heard," the seed abiding in you. Compare 1Jo 2:27, "the anointing abideth in you ... ye shall abide in Him." Having taken into us the living seed of the truth concerning the Father and the Son, we become transformed into the likeness of Him whose seed we have taken into us.