1 John 3:24

“And he that keepeth his commandments, &c.] Attends to those instructions and declarations concerning faith in Christ, and love to the brethren, and acts according to them: dwelleth in him, and he in them; that is, he dwells in Christ, and Christ dwells in him; the same is said of believing in Christ under the figurative expressions of eating his flesh, and drinking his blood, (see Gill on “<430656>John 6:56”); and hereby we know that he abideth in us; or dwelleth in us, as before, by the Spirit which he hath given us; which if understood of private Christians, as the preceding verses incline to, the sense is, that union to Christ, and the continuance of it, or his indwelling as a fruit of…”

“dwelleth in him--The believer dwelleth in Christ. and he in him--Christ in the believer. Reciprocity. "Thus he returns to the great keynote of the Epistle, abide in Him, with which the former part concluded" (Jo1 2:28). hereby--herein we (believers) know that he abideth in us, namely, from (the presence in us of) the Spirit "which He hath given us." Thus he prepares, by the mention of the true Spirit, for the transition to the false "spirit," Jo1 4:1-6; after which he returns again to the subject of love. Next: 1 John Chapter 4”

“And he that keepeth his commandments ... - See the notes at John 14:23. And hereby we know that he abideth in us - That is, this is another certain evidence that we are true Christians. The Saviour had promised John 14:23 that he would come and take up his abode with his people. John says that we have proof that he does this by the Spirit which he has given us. That is, the Holy Spirit is imparted to his people to enlighten their minds; to elevate their affections; to sustain them in times of trial; to quicken them in the performance of duty; and to imbue them with the temper and spirit of the Lord Jesus. When these effects exist, we may be certain that the Spirit of God is with us; for…”

“And he that keepeth his commandments - That thus believes and loves. Abideth in him, and God in him: and hereby we know that he abideth in us, by the Spirit which he hath given us - Which witnesses with our spirits that we are his children, and brings forth his fruits of peace, love, holiness. This is the transition to the treating of the Holy Spirit which immediately follows. Next: 1 John Chapter 4”

“he that: Jo1 3:22; Joh 14:21-23, Joh 15:7-10 dwelleth: Jo1 4:7, Jo1 4:12, Jo1 4:15, Jo1 4:16; Joh 6:54-56, Joh 17:21; Co1 3:16, Co1 6:19; Co2 6:16; Ti2 1:14 we: Jo1 4:13; Rom 8:9-17; Gal 4:5, Gal 4:6 Next: 1 John Chapter 4”