We are living here in mortality, and if we come to Christ and start living his laws and change our way of existence, we are born again. Paul expresses it by saying that we crucify the old man of sin. (See Romans 6:6 and Ephesians 4:22.) We die as pertaining to the things of this world and we become alive in Christ. We become members of his family.
When Alma the younger had his glorious experience and was born again—without any question he had been baptized in his youth but he had not been born again, he had not exercised the power to become a son of God—when this finally came, he received from the Lord the pronouncement that all mankind, men and women, people of every nation and kindred and tongue, had to be born again if they were to become inheritors of peace in this life and eternal life in the world to come.
And then he was counseled that they had to become new creatures. They had to become a new creation by the power of the Holy Spirit; their lives had to be changed. (See Mosiah 27:24–31 and Alma 5.) And that change is one in which people become alive to the things of righteousness; they die as pertaining to carnality and things that are vulgar, as to things that lead contrary to, and away from, the Lord, our Heavenly Father.
(Bruce R. McConkie, Households of Faith, Brigham Young University Speeches of the Year [Provo, 1 Dec. 1970], p. 4)