Lay hands suddenly on no man, neither be partaker of other men's sins: keep thyself pure.
Lay hands - i:e., ordain (1 Timothy 4:14; 2 Timothy 1:6; Titus 1:5). The connection is with 1 Timothy 5:19. The way to guard against scandals in presbyters is, be cautious as to the character of the candidate before ordaining him. This will apply to other church officers also. Thus, this clause refers to 1 Timothy 5:19, as next clause, "neither be partaker of other men's sins," refers to 1 Timothy 5:20. Ellicott understands it of receiving back into church fellowship, absolving, by laying hands on those who had been 'rebuked' (1 Timothy 5:20) and excommunicated (Matthew 18:17). But as in Acts 6:6; Acts 13:3; 1 Timothy 4:14; 2 Timothy 1:6, the laying on of hands is used of ordination, and there is no express reference to excommunication and absolution in the context, the ancient interpretation is best.
Suddenly - hastily. 1 Timothy 5:24-25 show that waiting is salutary.
Neither be partaker of other men's sins - by negligence in ordaining ungodly candidates; so becoming, in some degree, responsible for their sins. Or, there is the same transition from elders to all who sin, as in 1 Timothy 5:19-20. Be not a partaker in other men's sins by not 'rebuking them that sin before all:' alike those that are candidates for the presbytery, also all "that sin."
Keep thyself pure - "keep THYSELF." (emphatic) clear of OTHER men's sin, by not failing to rebuke them (1 Tim. 5:29). The transition is easy to 1 Timothy 5:23, concerning Timothy personally (cf. also 1 Timothy 5:24).