This verb means to do what is good or right, to act with virtue. In 2 Thessalonians 3:13, Paul exhorts, 'Do not grow weary in doing good (kalopoiountes).' The participle describes ongoing moral action—not a single good deed but a lifestyle of virtue. Paul's concern is that the Thessalonians might become discouraged or exhausted in their commitment to righteousness, perhaps frustrated by others' idleness or opposition. He urges perseverance in well-doing despite weariness or lack of visible reward.