The Doctrine and Covenants/Section 22
Revelation through Joseph Smith, Manchester, New York, April 1830. History of the Church 1:79-80.
1 Behold, I say unto you that all old covenants have I caused to be done away in this thing; and this is a new and an everlasting covenant, even that which was from the beginning.
2 Wherefore, although a man should be baptized an hundred times it availeth him nothing, for you cannot enter in at the strait gate by the law of Moses, neither by your dead works.
3 For it is because of your dead works that I have caused this last covenant and this church to be built up unto me, even as in days of old.
4 Wherefore, enter ye in at the gate, as I have commanded, and seek not to counsel your God. Amen.