Malachi is the last book of the Old Testament, written roughly four centuries before Christ. The temple Haggai and Zechariah pushed the people to finish is standing, but the excitement is gone. The book is built as a back-and-forth: the Lord makes a statement, the people push back with “Wherein?” (Malachi 1:2, 6–7; 2:17; 3:7–8; see also 3:13), and the Lord answers. It opens with “I have loved you,” and the people reply, in effect, “Prove it” (1:2). That honest, slightly defensive tone will sound familiar to teenagers, and that is the point: the Lord keeps answering and keeps inviting, “Return unto me, and I will return unto you” (3:7).
The priests offered blind, lame and sick animals and called the whole thing a weariness (1:8, 13). The Lord asks: would your governor accept that? He wants a pure offering (1:11), our real best, not leftovers. Then comes tithing: “Will a man rob God?” (3:8–12). For youth earning their first paychecks, this is practical. Tithing is one-tenth of our increase (Doctrine and Covenants 119:4). Elder David A. Bednar’s October 2013 talk “The Windows of Heaven” teaches that the promised blessings are often quiet and practical rather than a sudden flood of money. Near the end of each year, the bishop also meets with members for tithing declaration; families often go together.
Malachi ends with the Old Testament’s final promise: the Lord will send Elijah before the great and dreadful day of the Lord, and he will turn the hearts of the fathers and the children to each other (4:5–6). When Moroni visited Joseph Smith in 1823, Joseph was 17, the age of many in your class. Moroni quoted this prophecy with a difference: the Lord would reveal the priesthood by the hand of Elijah, and he would plant in the hearts of the children the promises made to the fathers (Joseph Smith—History 1:36–39). Elijah came to Joseph Smith and Oliver Cowdery in the Kirtland Temple on April 3, 1836, after the Savior appeared and accepted the temple, and committed the sealing keys (Doctrine and Covenants 110:13–16).
Connect this to where your youth are right now. “The promises made to the fathers” include the covenant God made with Abraham (Abraham 2:9–11). A patriarchal blessing declares a person’s lineage in the house of Israel and so ties them to those promises. Temple ordinances for their ancestors, family history, and their own future sealing all flow from Elijah’s keys. Be sensitive: some youth have complicated or painful family situations. Turning hearts includes the people who raise and love them now, ancestors they’ve never met, and the family they will one day build.