四分律刪繁補闕行事鈔 2.337

2.337

不舐食者，吐舌舐飯也。除病、被縛、手有泥垢膩汗，舌舐而取者。

Not licking food means sticking out the tongue to lick rice. Excepted are cases of illness, being bound, or having mud, dirt, grease, or sweat on the hands and licking it up with the tongue.