But ye, brethren, be not weary in well-doing (υμεις δε, αδελφοι, μη ενκακησητε καλοποιουντες). Emphatic position of υμεις in contrast to these piddlers. Μη and the aorist subjunctive is a prohibition against beginning an act (Robertson, Grammar, pp. 851-4). It is a late verb and means to behave badly in, to be cowardly, to lose courage, to flag, to faint, (εν, κακος) and outside of Luke 18:1 in the N.T. is only in Paul's Epistles (2. Thessalonians 3:13; 2. Corinthians 4:1; 2. Corinthians 4:16; Galatians 6:9; Ephesians 3:13). It occurs in Polybius. The late verb καλοποιεω, to do the fair (καλος) or honourable thing occurs nowhere else in the N.T., but is in the LXX and a late papyrus. Paul uses το καλον ποιειν in 2. Corinthians 13:7; Galatians 6:9; Romans 7:21 with the same idea. He has αγαθοποιεω, to do good, in 1. Timothy 6:18.