Who is Called the Church? 

20 And it came to pass that they did do all things even as Jesus had commanded them.

21 And they who were baptized in the name of Jesus were called the church of Christ. (3 Nephi 26)

How Many Churches Are There?

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 whore of all the earth. (1 Nephi 14)

All Believers Belong to the Church of God:

22 And thus, notwithstanding there being many churches they were all one church, yea, even the church of God; for there was nothing preached in all the churches except it were repentance and faith in God. (Mosiah 25)

Nothing Shall Destroy the Church Except Unrighteousness:

13 Nevertheless he cried again, saying: Alma, arise and stand forth, for why persecutest thou the church of God? For the Lord hath said: This is my church, and I will establish it; and nothing shall overthrow it, save it is the transgression of my people. (Mosiah 27)

The Church Shall Not Persecute Non-Believers:

21 Now there was a strict law among the people of the church, that there should not any man, belonging to the church, arise and persecute those that did not belong to the church, and that there should be no persecution among themselves. (Alma 1)