Притчи 27:2

2 Let another praise thee, and not thine own mouth; A stranger, and not thine own lips. The negative לא is with פיך, as in (Arab.) ghyra fyk, bound into one compact idea: that which is not thine own mouth (Fleischer), "not thine own lips," on the other hand, is not to be interpreted as corresponding to it, like אל־מות, Pro 12:28; since after the prohibitive אל, יהללוּך [praise thee] easily supplies itself. זר is properly the stranger, as having come from a distance, and נכרי he who comes from an unknown country, and is himself unknown (vid., under Pro 26:24); the idea of both words, however, passes from advena and alienigena to alius. There is certainly in rare cases a praising of oneself, which is authorized because it is demanded (Co2 11:18), which, because it is offered strongly against one's will, will be measured by truth (Pro 10:13); but in general it is improper to applaud oneself, because it is a vain looking at oneself in a glass; it is indecent, because it places others in the shade; imprudent, because it is of no use to us, but only injures, for propria laus sordet, and as Stobus says, οὐδὲν οὕτως ἄκουσμα φορτικὸν ὡς καθ ̓ αὑτοῦ ἔταινος. Compare the German proverb, "Eigenlob stinkt, Freundes Lob hinkt, fremdes Lob klingt" [= self-praise stinks, a friend's praise is lame, a stranger's praise sounds].

Note, 1. We must do that which is commendable, for which even strangers may praise us. Our light must shine before men, and we must do good works that may be seen, though we must not do them on purpose that they may be seen. Let our own works be such as will praise us, even in the gates, Phi 4:8. 2. When we have done it we must not commend ourselves, for that is an evidence of pride, folly, and self-love, and a great lessening to a man's reputation. Every one will be forward to run him down that cries himself up. There may be a just occasion for us to vindicate ourselves, but it does not become us to applaud ourselves. Proprio laus sordet in ore - Self-praise defiles the mouth.

27:2 The Hebrew word translated praise comes from the same root as “brag” in 27:1. Bragging (self-praise) is foolish.