The Spirit of the Lord witness through pondering and prayer those passages.
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Rec 3
20 Behold, I stand at the door, and knock: if any man hear my voice, and open the door, I will come in to him, and will sup with him, and he with me.
D&C 88
63 Draw near unto me and I will draw near unto you; seek me diligently and ye shall find me; ask, and ye shall receive; knock, and it shall be opened unto you.