For the source text click/tap here: Sukkah 12
To download, click/tap here: PDF
A sukkah fashioned by hollowing out an existing haystack is invalid. This disqualification is known as “taaseh velo min haasui,” which means you must create a valid sukkah and not fix an invalid one. This principle is derived from the verse “[Chag] hasukkot taaseh lecha” – “[the festival of] Sukkot you shall make for yourself.”
The principle of taaseh velo min haasui is derived from the fact that the word “sukkot” precedes the word “make.”
The Modzhitzer Rebbe, zt”l, writes that Chazal’s statement that one who learns a lot of Torah should not feel self-satisfied is also expressed in our gemara. “Make it, and do not use that which is already made.” תעשה—always consider yourself to be just beginning to serve Hashem. Nothing has been done, everything is yet to be accomplished. העשוי מן ולא—do not rest on your laurels and rely on that which you have already achieved.