When thou sittest to eat with a ruler, &c.— There are two evils to be avoided at the tables of the great: the one is, too much talking; the other, too much eating: the wise man exhorts his disciple to avoid both the one and the other by the phrase, put a knife to thy throat; "Repress your appetite, and your inclination to talk." Wine, company, and the gaiety which attends entertainments, often invite men to be too free in the use of meat and drink; and it is by these that kings frequently prove the fidelity and the secrecy of their confidants.
Monarchs, 'tis said, with many a flowing bowl, Search through the deep recesses of his soul, Whom for their future friendship they design; And put him to the torture in his wine. Hor. Ars Poet. ver. 435.
See also Sir 31:12-14. Schultens and some others render the second verse: For thou wilt put a knife to thy throat, if thou art given to appetite; i.e. "if thou dost not curb thy appetite, it will expose thee to as certain danger, as if a knife were at thy throat." The first and third verse's seem plainly to prove, that we must understand the phrase in the second as a caution against excess and intemperance.