Church manual states "more sure word of prophecy" is being "sealed up unto eternal life."
"New Testament Seminary Teacher Manual Lesson 146," The Church of Jesus Christ of Latter-day Saints, accessed October 19, 2021
2 Peter 1:19. “A more sure word of prophecy”
Modern revelation confirms and clarifies the meaning of the phrase “more sure word of prophecy” (2 Peter 1:19). Doctrine and Covenants 131:5 states, “The more sure word of prophecy means a man’s knowing that he is sealed up unto eternal life, by revelation and the spirit of prophecy, through the power of the Holy Priesthood.”
Faithful female as well as male members of the Church may obtain the blessing of having one’s calling and election made sure, or receiving the more sure word of prophecy.