James 3:18 (ESV) … “And a harvest of righteousness is sown in peace by those who make peace.”
Those who are possessed of the heavenly wisdom James called “peacemakers.” James’s focus on peacemaking returns to the very heart of the teachings of Jesus and his standards for discipleship. By another agricultural allusion, peacemakers act like a sower who sows the seed of peace. Like God, who sows the seed of the living Word (cf. Matt 13:19), believers are to sow peaceable deeds that will produce a harvest of righteousness. These acts that make for peace are the deeds of mercy, and this harvest is the good fruit mentioned in the previous verse.
The use of the words “produce” or “a harvest” in this connection is a marvelous image of the fruitfulness of a life of wisdom. Wisely sowing the seed of peace results in a multiplication of righteous deeds not only for the individual believer but also among the members of the entire church. A church that is rich in reconciling activities, that is, evangelism, the defense of the poor, counseling the troubled, offering hospitality to the stranger, providing shelter for the battered, sending gospel missionaries throughout the world, and many more, certainly reaps a rich harvest of righteousness. Wherever the church of Christ is doing these things, the kingdom of God is in evidence. This harvest precisely is what Jesus meant by the admonition to “seek first the kingdom of God and its righteousness” (Matt 6:33).