Reference for Shabbat 139:1
מאי שנא רישא ומאי שנא סיפא אמר רב ספרא כאן מידיעת שבת הוא פורש וכאן מידיעת מלאכה הוא פורש א"ל רב נחמן כלום פריש משבת אלא משום מלאכות וכלום פריש ממלאכות אלא משום שבת אלא אמר רב נחמן קרבן דחייב רחמנא אמאי אשגגה התם חדא שגגה הכא טובא שגגות הויין:
Wherein does the first clause differ from the second? — Said R. Safra: Here he would refrain on account of the knowledge that it is the Sabbath: whilst there he would refrain through the knowledge of the [forbidden] labor[s]. Said R. Nahman to him: Does one refrain from [action on] the Sabbath [for any other reason] save that the labours [are forbidden]; and does one refrain from labours for aught save because of the Sabbath?<span class="x" onmousemove="('comment',' If the matter is determined by what one would refrain from, the Sabbath and its forbidden labours are tantamount to the same thing, and there would be one law for both forms of ignorance. ');"><sup>1</sup></span> But said R. Nahman: for what does the Divine Law impose a sacrifice? For ignorance. There there is one fact of ignorance; here there are many facts of ignorance.<span class="x" onmousemove="('comment',' V. notes on the Mishnah 67b. ');"><sup>2</sup></span> HE IS LIABLE FOR EVERY SEPARATE LABOUR. Whence do we know the division of labors?<span class="x" onmousemove="('comment',' That a sacrifice is incurred for every separate labour, though they are all performed in one state of unawareness. ');"><sup>3</sup></span>