Malachi 3:1 - 18
ESV - 1 Behold, I send my messenger, and he will prepare the way before me. And the Lord whom you seek will suddenly come to his temple; and the messenger of the covenant in whom you delight, behold, he is coming, says the Lord of hosts. 2 But who can endure the day of his coming, and who can stand when he appears? For he is like a refiner's fire and like fullers' soap.
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