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The primary source in the Torah not to waste is derived from the passage that forbids cutting down a fruit tree when putting a city under siege. Yet, chazal understand that any form of wasting a useable item is included in this prohibition generally called Baal Tashchit.
- For example, it is forbidden to burn a useable shirt or break a vessel for no reason. 
- Rambam Sefer HaMitzvot (Lavin n. 57)
- Rambam Sefer HaMitzvot (Lavin n. 57), Rambam (Melachim 6:10)