Aṅguttara Nikāya
Tikanipātapāḷi
Tatiyapaṇṇāsakaṃ
Sambodhavaggo
Ruṇṇasuttaṃ
'This is crying, almsmen, in the discipline of what is noble, this what is: singing. This is madness, almsmen, in the discipline of what is noble, this what is: dancing. This is juvenile, almsmen, in the discipline of what is noble, this what is: excessively laughing showing teeth.
Therefor, almsmen, burn your bridges about singing, burn your bridges about dancing, Enough! Gladdened by the principle for you the existing smile is a measured smile.'