John Gill Reformed Baptist @doctorgill

And put a knife to thy throat,.... Refrain from too much talk at the table; give not too loose to thy tongue, but bridle it, considering in whose presence thou art; do not use too much freedom, either with the ruler or fellow guests; which, when persons have ate and drank well, they are too apt to do, and sometimes say things offensive to one...

Jamieson-Fausset-Brown Reformed @jfbcommentary

put a knife--an Eastern figure for putting restraint on the appetite.

Geneva Bible Notes Reformed @genevanotes

And put a knife to thy throat, if thou [art] a man given to appetite. (b) Bridle your appetite, as if by force and violence.