Jamieson, Fausset and Brown on Ephesians 6:24

24. Contrast the malediction on all who love Him not (1Co 16:22).

in sincerity--Greek, "in incorruption," that is, not as English Version, but "with an immortal (constant) love" [Wahl]. Compare "that which is not corruptible" (1Pe 3:4). Not a fleeting, earthly love, but a spiritual and eternal one [Alford]. Contrast Col 2:22, worldly things "which perish with the using." Compare 1Co 9:25, "corruptible ... incorruptible crown." "Purely," "holily" [Estius], without the corruption of sin (See on 1Co 3:17; 2Pe 1:4; Jude 10). Where the Lord Jesus has a true believer, there I have a brother [Bishop M'ikwaine]. He who is good enough for Christ, is good enough for me [R. Hall]. The differences of opinion among real Christians are comparatively small, and show that they are not following one another like silly sheep, each trusting the one before him. Their agreement in the main, while showing their independence as witnesses by differing in non-essentials, can only be accounted for by their being all in the right direction (Ac 15:8, 9; 1Co 1:2; 12:3).