"If there is no resurrection of the dead, Christ Himself has not been raised" (1 Cor 15:13). "And if Christ was not raised, your faith is worthless. You are still in your sins, and those who have fallen asleep in Christ are the deadest of the dead. If our hopes in Christ are limited to this life only, we are the most pitiable of men" (1 Cor 15:17-19). However, because Christ has risen and will raise from the dead those who live for Him, those who do not know and believe this "are the most pitiable of men" and have hopes limited to this life only.
How can those who don't believe in the risen Christ face death without despairing? They are "strangers to the covenant and its promise;" they are "without hope" (Eph 2:12). How can those who don't believe in Jesus, "the Resurrection and the Life" (Jn 11:25), live without trivializing life or seeing it as a cruel joke in which our deepest human desires are crushed in the finality of death? To believe that Jesus has risen and will raise us from the dead affects every breath, thought, love, desire, decision, and moment of our lives. Not to believe in the resurrection is to walk in fearful darkness.
Consequently, out of love for God and people, obey Jesus Who insists that we be witnesses to His resurrection (see Acts 4:33). Risk your life (see 1 Cor 15:30) to tell the ultimate good news of resurrection from the dead in the risen Christ.