Jamieson, Fausset and Brown on 2 Timothy 2:21

21. If a man ... purge himself from these--The Greek expresses "If one (for example, thou, Timothy) purify himself (so as to separate) from among these" (vessels unto dishonor).

sanctified--set apart as wholly consecrated to the Lord.

and meet--Some oldest manuscripts omit "and."

the master's--the Lord's. Paul himself was such a vessel: once one among those of earth, but afterwards he became by grace one of gold.

prepared unto every good work--(2Ti 3:17; Tit 3:1). Contrast Tit 1:16.