Verse 4
In himself alone, and not in another; that is, his sources of joy shall be within himself.

Verse 5
For every man, &c.; that is, his happiness must depend upon his own inward character.

Verse 6
Communicate; share with; that is, let the taught provide for the comfortable subsistence of their teachers.

Verse 7
Is not mocked; cannot be deceived.

Verse 12
To make a fair show in the flesh; to make an outward display of sanctity.

Verse 13
In your flesh; in your ceremonial observances.

Verse 17
The marks; the proofs that I am his. He refers, doubtless, to the marks of bodily injury which he had sustained in the service of Christ.