23:22כ״ג:כ״ב
1 א

לא תאחר לשלמו. שְׁלוֹשָׁה רְגָלִים, וּלְמָדוּהוּ רַבּוֹתֵינוּ מִן הַמִּקְרָא (ראש השנה ד'):

לא תאחר לשלמו [WHEN THOU SHALT VOW A VOW UNTO THE LORD THY GOD] THOU SHALT NOT DELAY TO PAY IT — beyond three festivals after the vow has been made. Our Rabbis have deduced it (the fact that one does not transgress the prohibition before three festivals elapse) from a Scriptural text (Rosh Hashanah 4b).