Agathopoieo (15), "to do good" (agathos, "good," poieo, "to do"), is used (a) of such activity in general, <1 Pet. 2:15>, "well-doing"; <v. 20>, "do well"; <3:6,17; 3 John 11>, "doeth good"; (b) of "acting for another's benefit," <Mark 3:4; Luke 6:9,33,35>.
(from Vine's Expository Dictionary of Biblical Words)
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