As I was reading the scripture that I just posted for my "Book of Mormon Sampler" feature, I was struck in particular by the phrase, "and if ye will lay hold upon every good thing, and condemn it not, ye certainly will be a child of Christ." I immediately thought of this phrase from a scripture from Isaiah, "...when thou shalt make his soul an offering for sin, he shall see his seed...". (Isaiah 53:10) When we take advantage of his offering for sin on our behalf, then we become his children. In this way, he begets us spiritually. In this way, he becomes our Father.
In the Book of Mormon we have an account of a people who were taught the gospel of Jesus Christ, and desired to covenant to follow him. They were given this counsel, " And now, because of the covenant which ye have made ye shall be called the children of Christ, his sons, and his daughters; for behold, this day he hath spiritually begotten you; for ye say that your hearts are changed through faith on his name; therefore, ye are born of him and have become his sons and his daughters." (Mosiah 5:7)
I do believe that this is not a one time act, but a lifelong pursuit. Once we have taken upon us the name if Christ, and have covenanted to keep his commandments, we must continually repent and strive to keep the commandments so that at the judgment day we can be found among those who are called "the children of Christ".