Mosiah 15:21 - 15:25
Mosiah 15:21 And there cometh a resurrection, even a first resurrection; yea, even a resurrection of those that have been, and who are, and who shall be, even until the resurrection of Christ—for so shall he be called.
The resurrection of all the righteous is called the first resurrection.
Mosiah 15:22 And now, the resurrection of all the prophets, and all those that have believed in their words, or all those that have kept the commandments of God, shall come forth in the first resurrection; therefore, they are the first resurrection.
This will consist of the prophets and those who followed them and kept the commandments of God.
Mosiah 15:23 They are raised to dwell with God who has redeemed them; thus they have eternal life through Christ, who has broken the bands of death.
These folks will be able to live with God throughout the eternities because of Christ.
Mosiah 15:24 And these are those who have part in the first resurrection; and these are they that have died before Christ came, in their ignorance, not having salvation declared unto them. And thus the Lord bringeth about the restoration of these; and they have a part in the first resurrection, or have eternal life, being redeemed by the Lord.
One of the groups having a part of the first resurrection will be those who did not know of the Savior or of the gospel in this life. Those who lived in ignorance will be redeem by the Lord without any preconditions required of them.
Mosiah 15:25 And little children also have eternal life.
Little children also fall into this group.