אַל־תַּאֲמִ֣ינוּ בְרֵ֔עַ אַֽל־תִּבְטְח֖וּ בְּאַלּ֑וּף מִשֹּׁכֶ֣בֶת חֵיקֶ֔ךָ שְׁמֹ֖ר פִּתְחֵי־פִֽיךָ׃
Janganlah kamu percaya kepada teman, janganlah kamu mengandalkan sahabat karib; jagalah pintu mulutmu terhadap dia yang berbaring di pangkuanmu.
Rashi
Believe not a friend [This is to be understood] according to its apparent meaning. But our Sages explained it as referring to the Most High. Do not sin and say that the Holy One, blessed be He, is our Friend, and He will forgive us. [from Hagiga 16a]
Rashi
the openings of your mouth Heb. פִּתְחֵי. The words of your mouth, the openings of your mouth.