He lives!

The Prophet Joseph Smith's testimony (JS-H 1:16-17):

I saw a pillar of light exactly over my head, above the brightness of the sun, which descended gradually until it fell upon me. . . . When the light rested upon me I saw two Personages, whose brightness and glory defy all description, standing above me in the air. One of them spake unto me, calling me by name and said, pointing to the other—This is My Beloved Son. Hear Him!

The testimony of the Prophet Joseph Smith and Sidney Rigdon (D&C 76:22-23):

22 And now, after the many testimonies which have been given of him, this is the testimony, last of all, which we give of him: That he lives!
23 For we saw him, even on the right hand of God; and we heard the voice bearing record that he is the Only Begotten• of the Father—

The testimony of His living apostles (The Living Christ):

. . . We bear testimony, as His duly ordained Apostles—that Jesus is the Living Christ, the immortal Son of God. He is the great King Immanuel, who stands today on the right hand of His Father. He is the light, the life, and the hope of the world. His way is the path that leads to happiness in this life and eternal life in the world to come. God be thanked for the matchless gift of His divine Son.