John closed with a final admonition. Departure from the true God and His teaching constitutes idolatry. As contradicting God is really calling Him a liar ( 1 John 1:10), so departing from God is really idolatry. Departing from God includes leaving apostolic teaching and practice, behaving as a child of Satan rather than as a child of God. [source][source][source]
"False teaching is ultimately "apostasy from the true faith." To follow after it is to become nothing better than an idol worshiper, especially if it is a matter of the truth of one"s conception of God. The author is blunt. The false teachers propose not the worship of the true God, made known in his Son Jesus, but a false god-an idol they have invented." [1][source]
This verse is a New Testament restatement for Christians of the first commandment God gave the Israelites in the Decalogue ( Exodus 20:3-5; Deuteronomy 5:7-9). [source][source][source]
Context Summary
1 John 5:13-21 - Ask According To His Will
We know that we have eternal life. The rope is in our hand bearing us onward, but its ends are hidden from view in the past and in the future. We also know that God hears us when we comply with the conditions of true prayer. We know, moreover, that we can become the medium through which the life of God passes to others. Thus the humblest child may have power with God and man.
The Only-Begotten keeps the begotten. Evil can no more touch them than blight could reach the bush in the wilderness that was bathed in the celestial fire. Who would go back to the world? Enumerate and press to heart these four items of positive knowledge; but beware lest what is legitimate and natural in itself may become an idol. Love, knowledge, abiding, conquering-these are the keynotes of this wonderful letter. [source]
Chapter Summary: 1 John 5
1He who loves God loves his children, and keeps his commandments; 3which to the faithful are not grievous 9Jesus is the Son of God; 14and able to hear our prayers
Greek Commentary for 1 John 5:21
Yourselves [εαυτα] Neuter plural reflexive because of τεκνια teknia The active voice πυλασσετε phulassete with the reflexive accents the need of effort on their part. Idolatry was everywhere and the peril was great. See Acts 7:41: 1 Thessalonians 1:9 for this word. [source]
Keep yourselves [φυλάξατε ἑαυτὰ] The exact phrase is not found elsewhere in the New Testament. See 2 Peter 3:17. Rev., rightly, guard. See on 1 Peter 1:4. [source]
Idols [εἰδώλων] Strictly, images. The command, however, has apparently the wider Pauline sense, to guard against everything which occupies the place due to God. [source]
Reverse Greek Commentary Search for 1 John 5:21
1 John 2:1My little children [τεκνία μου] Τεκνίον , little child, diminutive of τέκνον childoccurs in John 8:33; 1 John 2:12,1 John 2:28; 1 John 3:7,1 John 3:18; 1 John 4:4; 1 John 5:21. This particular phrase is found only here (best texts omit my in 1 John 3:18). Used as a term of affection, or possibly with reference to the writer's advanced age. Compare Christ's word, παιδία children(John 21:5) which John also uses (1 John 2:13,1 John 2:18). In the familiar story of John and the young convert who became a robber, it is related that the aged apostle repaired to the robber's haunt, and that the young man, on seeing him, took to flight. John, forgetful of his age, ran after him, crying: “O my son why dost thou fly from me thy father? Thou, an armed man, - I, an old, defenseless one! Have pity upon me! My son, do not fear! There is still hope of life for thee. I wish myself to take the burden of all before Christ. If it is necessary, I will die for thee, as Christ died for us. Stop! Believe! It is Christ who sends me.” [source]
Greek Commentary for 1 John 5:21
Neuter plural reflexive because of τεκνια teknia The active voice πυλασσετε phulassete with the reflexive accents the need of effort on their part. Idolatry was everywhere and the peril was great. See Acts 7:41: 1 Thessalonians 1:9 for this word. [source]
The exact phrase is not found elsewhere in the New Testament. See 2 Peter 3:17. Rev., rightly, guard. See on 1 Peter 1:4. [source]
Strictly, images. The command, however, has apparently the wider Pauline sense, to guard against everything which occupies the place due to God. [source]
Reverse Greek Commentary Search for 1 John 5:21
Τεκνίον , little child, diminutive of τέκνον childoccurs in John 8:33; 1 John 2:12, 1 John 2:28; 1 John 3:7, 1 John 3:18; 1 John 4:4; 1 John 5:21. This particular phrase is found only here (best texts omit my in 1 John 3:18). Used as a term of affection, or possibly with reference to the writer's advanced age. Compare Christ's word, παιδία children(John 21:5) which John also uses (1 John 2:13, 1 John 2:18). In the familiar story of John and the young convert who became a robber, it is related that the aged apostle repaired to the robber's haunt, and that the young man, on seeing him, took to flight. John, forgetful of his age, ran after him, crying: “O my son why dost thou fly from me thy father? Thou, an armed man, - I, an old, defenseless one! Have pity upon me! My son, do not fear! There is still hope of life for thee. I wish myself to take the burden of all before Christ. If it is necessary, I will die for thee, as Christ died for us. Stop! Believe! It is Christ who sends me.” [source]