Albert Barnes on John 6:56

Dwelleth in me. Is truly and intimately connected with me. To dwell or abide in him is to remain in the belief of his doctrine, and in the participation of the benefits of his death. Comp. Jn 15:1-6, 17:21-23.

I in him. Jesus dwells in believers by his Spirit and doctrine. When his Spirit is given them to sanctify them; when his temper, his meekness, his humility, and his love pervade their hearts; when his doctrine is received by them and influences their life, and when they are supported by the consolations of the gospel, it may be said that he abides or dwells in them.

(t) "dwelleth" Jn 15:4, 1Jn 3:24, 4:15,16