Summary

Talmud (Rodkinson Edition) — Book 1…

A general rule was laid down concerning the observation of the Sabbath. One who had entirely forgotten the principle of Sabbath, and had performed many kinds of work on many Sabbath days, is liable for but one sin-offering. How so? A child which was captured by idolaters and a proselyte remaining with idolaters, who had performed many acts of labor on different Sabbaths, are liable for but one sin-offering; and also for the blood or (prohibited) fats which he has consumed during the whole time, and even for worshipping idols during the whole time, he is liable for only one sin-offering.
Source: Wikisource

Talmud (Rodkinson Edition) — Book 1…

We must assume that although cognizant of the (day being) Sabbath, one forgot which acts of labor (were prohibited) . And this is correct only in accordance with R. Johanan, who holds: "If one is ignorant of what acts of labor constitute (sin punishable with) Karath (being 'cut off') , and commits one of those acts even intentionally, he is bound to bring a sin-offering only." And such an instance can be found in case one knows that those acts of labor were prohibited, at the same time being ignorant of that punishment which is Karath.
Source: Wikisource

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