They shall be called
Children of God.”
μακάριοι οἱ εἰρηνοποιοί, ὅτι αὐτοὶ υἱοὶ Θεοῦ κληθήσονται.
The happy, blessed, and fortunate ones (μακάριοι) would be those who made peace (οἱ εἰρηνοποιοί). The reward for these peacemakers would be that they would be called children or sons of God (ὅτι αὐτοὶ υἱοὶ Θεοῦ κληθήσονται). It was not enough to be a peaceful person, you had to make or be an artisan of peace, not just let it happen. These peacemakers would be like the sons or children of God. This comment about peacemakers was unique to Matthew since there is no equivalent in Luke. In fact, this is the only place in the Bible where there is any mention of peacemakers at all.