In the posts linked below I will distinguish between the "gospel of Mormonism" and other sectarian versions of Creedal-Christianity, where humor, joy and laughter are often absent or rejected. The fact is the New Testament gospels actually never mention Jesus smiling or laughing, although D. Elton Trueblood tried to argue in his book The Humor of Christ that Jesus told jokes and had a sense of humor. But only in Joseph Smith's restored gospel does Jesus appear smiling to his disciples in 3 Nephi 19:25, 30.
In Mormonism you have a more joyful representation of the gospel in that the life in the flesh is not to be despised, because all flesh is composed of spirit-matter (see D&C 131: 7-8) and so that you do not have this sour framework of "spirit against flesh" since the fleshly body itself is spiritual, instincts and all; including laughter and "dionysian" fun and celebration. So that rather the false ideal of sour faced somber piety, seeking to repress all joy in the sensory body, Joseph Smith "said ... to Mr. stout that Adam did not commit sin in eating the fruit" in 1841. For Adam only transgressed, so we are not as humans cursed with a permanesnt "Sinful flesh," that is Augustinian Original Sin, which is nonsense (see Article #2). Joseph Smith instead dictated new scripture that declared that Adam was a mighty Archangel and he taught that Adam recieved the priesthood prior to earth. This radically shifted the framework from the sectarian view of cursed flesh neeing to escape the body -- leading to sour faced self-flagellating bodily escapist "pillar saints" -- with Joseph’s doctrine instead that Adam fell upward so that mankind would learn happiness through opposion and experience joy in a body of flesh (see 2 Nephi 2: 25). This meant that Adam's act was part of the plan all along, for pre-existence spirits to gain bodies of flesh in order that they would have joy in their bodies of flesh! In fact, God the Father himself is an embodied being composed of celestialized flesh and bone (see D&C 130:22); and rather than demanding extreme repression like the pillar saints, Joseph Smith explained that actually "God is more liberal in his views"; and the same fun and joyful "sociality" among us here as humans will exist among us in the heavens among the Gods (see D&C 131: 2; Abraham 4; D&C 132).
For more on Joseph Smith's sense of humor and joyful sociality see these links below:
