Does the Gospel refer to all revealed truth?

The gospel in the Book of Mormon refers to the doctrine of Christ. It does not refer to all revealed truths, but specifically to the way and means by which all must come unto the Savior in order to be saved. As outlined by Jesus to his disciples, His gospel includes faith in Christ and sincere repentance of sins. Those who receive the sacred covenant of baptism are promised the gift of the Holy Ghost and if they endure to the end will be saved in his Kingdom at the last day. Although the Gospel does not refer to all truths and teachings revealed through God’s prophets, those who receive the gift of the Holy Ghost are promised that additional precepts, truths, teachings, and even scriptures will to be revealed in the Lord’s due time, “line upon line,” through God’s appointed prophets by means of the Holy Ghost (2 Nephi 27:10–11; 28:26–31; 29:8–14; 30:17–18; 3 Nephi 26:6–11; Mormon 8:12; Ether 4:13–16).