Mishnah 13 - Chapter 3 - Pirkei Avot

R. Akiva says: Laughter and light-headedness predispose to licentiousness. Masoreth (tradition) is a fence to Torah. [The (oral) masoreth passed on to us by the sages of the "defective" and "superfluous" readings in the Torah are a fence and strengthening of the written law. For through them we understand how to perform several mitzvoth, as in "basukkoth," "basukkoth" "basukkoth," two defective and one superfluous — whence we learn to rule a succah with three walls kasher, and as in "the festivals of the L rd which (ATM) you shall declare," which is written defective (to be pronounceable as "atem" ("you"), to teach: "you" (declare them) — even unwittingly; "you" — even deliberately; "you" — even mistakenly] Ma'asroth (tithes) are a fence to wealth, [it being written (Deuteronomy 14:22): "asser t'asser" — tithe so that you become rich ("titasher").] Vows are a fence to separation. [When one begins (a regimen of) separation and he fears lest he transgress, he takes it upon himself as a vow that he will not do such and such and thereby suppresses his inclination.] A fence for wisdom is silence. [What are we speaking of? If silence from words of Torah, it is written (Joshua 1:8): "And you shall meditate (lit., "speak") in it day and night, etc." If silence from talebearing, slander, and cursing — this is (interdicted) by the Torah! We must be speaking then of silence from permitted speech between a man and his neighbor — that one should minimize such speech as far as possible. And it is in this regard that Solomon said (Proverbs 17:28): "Even a fool who keeps quiet is regarded as a sage."]