New Defender's Study Bible Notes
2:28 little children. This exhortation is addressed specifically to new Christians, but it surely applies just as urgently to all Christians.
2:28 when he shall appear. If we “love His appearing” (II Timothy 4:8) and are “looking for Him” to “appear the second time” (Hebrews 9:28), then we will naturally be careful to seek to please Him daily in our thoughts, words and deeds, as well as being diligent in studying His Word.
2:28 ashamed before him. It will not mean loss of salvation, but rather shame and loss of confidence if we are behaving inconsistently when Christ returns. Note also Matthew 24:42-46; II Peter 3:11.