The Buddha and the act of smiling Namo tassa Bhagavato Arahato Samma Sambuddhassa.
Even though it may at first hand appear to be a shallow subject and inquiry, I happen to find it of relevance to the practice and wondered about it.
How prevalent was the Buddha's smiling ?
As I was starting to read Thanissaro Bhikkhu's &quot;The Buddha Smiles&quot;, it is stated :

The Pali Canon has a reputation for being humorless. And it’s easy to
see why. In some of its passages, the Buddha seems to regard humor in
a bad light. For instance, in the Wailing Discourse (AN 3:107) he
refers to “laughing excessively, showing one’s teeth,” as a form of
childishness, and counsels that a monk, when feeling joy in the
Dhamma, should simply smile. His instructions to Rāhula in MN 61 note
that one shouldn’t tell a deliberate lie, “even in jest.” A passage in
the Vinaya (Sk 51) tells of a monk, formerly an actor, who made a joke
about the Saṅgha. The Buddha, in response, made it an offense for a
monk to tell a joke not only about the Saṅgha, but also about the
Buddha or Dhamma.
There is also the famous verse in the Dhp 146 that seems aimed at
squelching all forms of merriment:
&quot;What laughter, why joy, when constantly aflame? Enveloped in darkness,
don’t you look for a lamp?&quot;
And then there’s the fact that the Buddha himself rarely smiles in the
Canon, and when he does, the reasons for his smile are never
hilarious.

(the emphasize in the quoted passages is a making of mine)
Yet, I started to also read Walpola Rahula's &quot;What the Buddha taught&quot; in which I can read the following :

The Buddha was never melancholy or gloomy. He was described by his
contemporaries as ‘ever-smiling’ (mihitapubbamgama). In Buddhist
painting and sculpture the Buddha is always represented with a
countenance happy, serene, contented and compassionate.

There seems to be a divergence in the two quoted passages as to whether he was &quot;ever-smiling&quot; or only in rare occasions.
In Bhante Vimalaramsi's teaching the act of smiling within one's practice is quite present yet I cannot recall from what I read in the suttas the mentioning of smiling.
I'd appreciate learning more about it.
(If such a question is indeed irrelevant please kindly let me know and I'll delete the question).
With metta.
The Buddha smiles many times in the suttas, in fond remembrance of experiences that brought great wisdom.

MN83:2.1: Then the Buddha smiled at a certain spot.

The Buddha does not smile at the suffering of others. His smiles are never cruel. His smiles are for the remembrance of great wisdom and insight that can be shared. The Buddha smiles for us all, never against any.

MN83:21.16: Ānanda, I say to you:
MN83:21.17: ‘You all should keep up this good practice that I have founded. Do not be my final men.’”
MN83:21.18: That is what the Buddha said.
MN83:21.19: Satisfied, Venerable Ānanda was happy with what the Buddha said.
(END)