Mosiah 15:11-12 - Who is Christ's seed?

11 Behold I say unto you, that whosoever has heard the words of the prophets, yea, all the holy prophets who have prophesied concerning the coming of the Lord—I say unto you, that all those who have hearkened unto their words, and believed that the Lord would redeem his people, and have looked forward to that day for a remission of their sins, I say unto you, that these are his seed, or they are the heirs of the kingdom of God.

12 For these are they whose sins he has borne; these are they for whom he has died, to redeem them from their transgressions. And now, are they not his seed?

Those who accept God's word and are baptized into his church become heirs to the kingdom of God. Every person baptized into the church becomes a part of Abraham's posterity and enjoys the blessings of the Abrahamic covenant.

We cannot become like Christ and receive the spiritual blessings of being God's seed if we are not willing to do our part. Bruce C. Hafen of the first Quorum of the Seventy said, "The Savior’s grace blesses [us] if we do our part. . . . We need grace both to overcome sinful weeds and to grow divine flowers. We can do neither one fully by ourselves. But grace is not cheap. . . .If we desire 'all that [the] Father hath' (D&C 84:38),  God asks all that we have. To qualify for such exquisite treasure, in whatever way is ours, we must give the way Christ gave—every drop He had: 'How exquisite you know not, yea, how hard to bear you know not' (D&C 19:15). Paul said, 'If so be that we suffer with him,' we are 'joint-heirs with Christ' (Romans 8:17). All of His heart, all of our hearts" (Ensign, "The Atonement, All for All," May 2004).

So we must do everything in our power to live righteously if we want to receive of God's grace. However, this does not mean God will not bless us along the way. The reason Christ suffered the atonement was so that He could understand all of our trials, pains, sufferings, etc. He suffered so that He could help us along the way. He isn't going to watch us struggle on our own until we're about to give up--He is right by our side the whole way.

We will receive the greatest blessings of the Abrahamic covenant if we keep our end of our covenants with God. We must keep our promises to follow His commandments and stand as a witness of God at all times and in all things and in all places, and in return God will bless us with His Spirit to guide us. We will be more in tune with the Spirit and more able to recognize God's hand in our lives.