Reference for Beitzah 8:4

והא קא מבטל איסורא לכתחלה ותנן אין מבטלין איסור לכתחלה הני מילי בדאורייתא אבל בדרבנן מבטלין

But that would be annulling a prohibition ab initio! [Since the forbidden would be annulled by the majority permitted wood]. As it is taught [in a Mishnah]: "We do not annul a prohibition ab initio!" These words are with a Toraitic [prohibition], but for a rabbinic we do annul.

Explore reference for Beitzah 8:4. In-depth commentary and analysis from classical Jewish sources.