[2 John 1:8-9]:
(v. 8) "Watch out that you do not lose what you have worked for, but that you may be rewarded fully.
[Notice that rewards, not salvation are in view here. Salvation is a free gift for which one does not work, (Ro 3:21-24; Eph 2:8-9). Rewards on the other hand are something a believer is to work for and can lose if one does not continue in the teaching of Christ]
9) Anyone who runs ahead and does not continue in the teaching of Christ does not have God; whoever continues in the teaching has both the Father and the Son."
[Any believer since this letter addresses believers, (vv. 1-2) who does not continue in the teaching of Christ does not have God, i.e., does not have God in his experience. He is doing without God in his lifestyle. This does not mean that he does not have God re: eternal life. The focus is his behavior not his position re: eternal life.]
[Compare 1 Jn 2:3-6]:
3) "We know that we have come to know Him if we obey His commands.
[Notice that a believer comes to know Christ, (v. 2), if he obeys His commands. Although one may be saved, one does not come to know Christ in his experience until one is obedient to what He has commanded]
4) The man who says, "I know him," but does not do what he commands is a liar, and the truth is not in him.
5) But if anyone obeys his word, God's love is truly made complete in him. This is how we know we are in him:
6) Whoever claims to live in him must walk as Jesus did."
[So a believer lives in Jesus while he walks as Jesus walked. This is a matter of fellowship not of salvation.]