2 Nephi 28
3 For it shall come to pass in that day that the churches which are built up, and not unto the Lord, when the one shall say unto the other: Behold, I, I am the Lord’s; and the others shall say: I, I am the Lord’s; and thus shall every one say that hath built up churches, and not unto the Lord—
Mormons who believe their church's teachings assume that they have entered the path to eternal life by being baptized.
1 Nephi 14
10 And he said unto me: Behold there are save two churches only; the one is the church of the Lamb of God, and the other is the church of the devil; wherefore, whoso belongeth not to the church of the Lamb of God belongeth to that great church, which is the mother of abominations; and she is the harlot of all the earth.
Doctrine and Covenants 1
29 And after having received the record of the Nephites, yea, even my servant Joseph Smith, Jun., might have power to translate through the mercy of God, by the power of God, the Book of Mormon.
30 And also those to whom these commandments were given, might have power to lay the foundation of thischurch, and to bring it forth out of obscurity and out ofdarkness, the only true and living church upon the face of the whole earth, with which I, the Lord, am well pleased, speaking unto the church collectively and not individually—
31 For I the Lord cannot look upon sin with the least degree of allowance;
32 Nevertheless, he that repents and does the commandments of the Lord shall be forgiven;