1Jo 5:16-21 | TNotes | STEP | 5:16 Sins that lead to death are those involving apostasy (see Matt 12:31-32 ; Heb 6:4-6 ). In the context of this letter, apostasy involves leaving the apostolic faith and joining a heretical, anti-Christian movement such as those denounced in John’s letters.

5:16 ^a Sins that lead to death are those involving apostasy (see Matt 12:31-32 ^b; Heb 6:4-6 ^c). In the context of this letter, apostasy involves leaving the apostolic faith and joining a heretical, anti-Christian movement such as those denounced in John’s letters.
5:17 ^d not every sin leads to death: Those sins that do not involve ultimate apostasy can end in repentance and restoration (see Jas 5:20 ^e).
5:20 ^f The NLT interprets the phrase the true God as referring to God, since the next phrase refers to his Son, Jesus Christ. John is also saying that Jesus Christ is the only true God (see John 1:1 ^g, 18 ^h; 20:28 ⁱ; Rom 9:5 ^j; Titus 2:13 ^k; 2 Pet 1:1 ^l).

• To have fellowship with Jesus Christ is to have eternal life, because he is eternal life (1 Jn 5:12 ^m; see John 1:4 ⁿ; 3:16 ^o; 14:6 ^p; 20:31 ^q).
5:21 ^r In closing, John exhorts his flock to keep away from anything that might take God’s place in your hearts (literally keep yourselves from idols). In the context of 1 John, the primary idol would be any false teaching that takes people away from Jesus Christ, who is at once fully man and fully God.