Commentary for Avodah Zarah 37:10

ואמר רבא לעולם ליגריס איניש ואע"ג דמשכח ואע"ג דלא ידע מאי קאמר שנאמר (תהלים קיט, כ) גרסה נפשי לתאבה גרסה כתיב ולא כתיב טחנה

Rava also said: A person should always recite, even though he is liable to forget and even if he does not fully understand all the words which he says, as it is said, “My soul recites for desire of Your rules at all times” (Psalms 119:20). “Recites” is what Scripture says, it does not say “grinds.”

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