Doctrine and Covenants 1:38

What I the Lord have spoken, I have spoken, and I excuse not myself; and though the heavens and the earth pass away, my word shall not pass away, but shall all be fulfilled, whether by mine own voice or by the voice of my servants, it is the same.

From Kolob — a Bible & scripture knowledge graph. See every cross-reference and General Conference talk that cites this verse.