The threefold greeting seems more tailored for the occasion than standardized for general use. “Mercy” reappears three times in the closing appeal (vv. 21–23). Peace is longed for in a situation plagued by grumblers, malcontents, and schismatics (vv. 16, 19). And the love of God is the dwelling place of the believers (vv. 1, 21). The greeting, then, is more than a greeting; even in its brevity it anticipates the affirmation, the polemic, and the exhortation in the body of the letter.
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