Q: How do we know Yaakov Avinu was an environmentalist?
"[Yaakov] took his two wives, his two handmaids, and his eleven sons and he crossed the ford of Yabbok. And he took them and brought them across the stream, and brought across that which was his. [But afterwards] Yaakov was left alone..." (Genesis 32:23-25)
"—[Why did Yaakov stay behind?] He forgot PACHIM KETANIM and returned to pick them up" (Rashi)
"Pachim" means "cans" in modern Hebrew, so clearly was picking up the trash he had left behind the first time!