Jamieson, Fausset and Brown on Hebrews 13:9

9. about--rather, as oldest manuscripts read, "carried aside"; namely, compare Ep 4:14.

divers--differing from the one faith in the one and the same Jesus Christ, as taught by them who had the rule over you (He 13:7).

strange--foreign to the truth.

doctrines--"teachings."

established with grace; not with meats--not with observances of Jewish distinctions between clean and unclean meats, to which ascetic Judaizers added in Christian times the rejection of some meats, and the use of others: noticed also by Paul in 1Co 8:8, 13; 6:13; Ro 14:17, an exact parallel to this verse: these are some of the "divers and strange doctrines" of the previous sentence. Christ's body offered once for all for us, is our true spiritual "meat" to "eat" (He 13:10), "the stay and the staff of bread" (Is 3:1), the mean of all "grace."

which have not profited--Greek, "in which they who walked were not profited"; namely, in respect to justification, perfect cleansing of the conscience, and sanctification. Compare on "walked," Ac 21:21; namely, with superstitious scrupulosity, as though the worship of God in itself consisted in such legal observances.