Artistically the Buddha is often represented with a slight smile. Jesus is, too, in some paintings, for instance, in the serene and famous Head of Christ by Warner Sallman (1892-1968). I looked online for other pictures but the one I liked best (one that was natural-seeming and not "forced" in depicting Jesus' happiness), was actually an old stand-by, often seen in churches: Head of Christ by Richard Hook (1914-1975).
And, of course, there is the good old "Buddy Christ" from the movie Dogma: a grinning, winking Jesus giving a big thumbs-up. So many artistic depictions of Christ are solemn, stern, or serene but unsmiling.
Do accounts of Jesus' life mention his smile or laughter? Unfortunately, none of the canonical gospels do. We have ten verses altogether in non-canonical writings like the Gospel of Philip and the Apocryphon of John. Ricky Alan Mayotte, who has collected Jesus' teachings in the canonical and non-canonical writings, lists these verses. Here are four:
"But he who stands near him is the living Savior, the first in him, whom they seized and released, who stands joyfully looking at those who did him violence, while they are divided among themselves. Therefore he laughs at their lack of perception, knowing that they are born blind" (The Apocalypse of Peter).
"The Savior laughed and said to them, What are you thinking about? Why are you perplexed?" (The Sophia of Jesus Christ)
"And I said, 'Lord, where will the souls of these go when they have come out of their flesh?' And he smiled and said to me, The soul in which the power will become superior to the despicable spirit, she is strong and she flees from evil" (The Apocryphon of John)
"But I [Jesus] laughed joyfully when I examined his empty glory...And I was laughing at their ignorance" (The Second Treatise of the Great Seth)
In such writings, his laughter and smiles are ironic and knowing, rather than reflecting joie de vivre.
If you think strictly in terms of Jesus' atoning work, you might argue that the suffering of Jesus for our salvation takes precedence over his happiness. And yet that seems limiting, for didn’t Jesus have a broad, full (though short) life filled with all the emotions we experience? Certainly Jesus loved, and one needs psychological security and depth to be able to love as he did. Joy and laughter, too, require a sense of security. Not only that, but Jesus wanted his joy to be in the disciples, so their joy would be complete (John 15:11). We should read that verse and think of real joy in Jesus' voice, not the stern instructiveness with which we sometimes hear the words read in church.
1. Ricky Alan Mayotte, The Complete Jesus (South Royalton, VT: Steerforth Press, 1997), 149-150.