מֵפִ֣יץ וְ֭חֶרֶב וְחֵ֣ץ שָׁנ֑וּן אִ֥ישׁ עֹנֶ֥ה בְ֝רֵעֵ֗הוּ עֵ֣ד שָֽׁקֶר׃
Seperti gada, pedang, dan anak panah yang tajam, demikianlah orang yang memberikan kesaksian palsu terhadap sesamanya.
Rabbeinu Bahya
ושננתם לבניך, “you will teach them diligently to your children.” The word שנון denotes something “sharp” like the blade of a sharp sword. The word occurs in connection with the tip of an arrow, i.e. חץ שנון, Proverbs 25,18. The idea behind this phraseology is that if your children will ask you about the meaning of these laws you should be able to answer them immediately, without stuttering.
Ibn Ezra
repeat them over from “a sharp arrow” [Proverbs 25: 18] — and it is well known that an arrow becomes sharp only after continuous, repeated sharpening. From this we see that the essence of Man is the service of God ; and that one serves God by recognizing His works. The Exegetes, upon whom we all rely, have transmitted to us the prescribed times for the reading of the Shma ‘:
Rashi
I am sated with the burnt-offerings of rams This is similar to: “Lest he have too much of you and hate you,” (Proverbs 25:18).
Rashi
For my heart was in ferment Before I saw this downfall with the holy spirit, my heart was in ferment because the way of the wicked prospered, and my mind was on edge (אשתונן), an expression of a sharpened sword (שנון). When it is reflexive, the “tav” is placed in the middle of the radical, as is the case of every word whose radical commences with “shin.”