This adverb introduces a sharp contrast, marking something as the opposite of what might be expected or what was just mentioned. It's a contracted form (tounantion from to enantion) that intensifies the reversal. All three New Testament uses appear in Paul and Peter, introducing surprising reversals: forgiving instead of punishing, accepting rather than rejecting, blessing rather than cursing. The phrase signals that God's ways often run counter to human instinct and social convention.