It is narrated from Sayyiduna Salamah bin al-Muhabbiq (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) was on a journey. He came to a hanging waterskin and drank water from it. It was said: This is (made from) the skin of a dead animal. He (peace and blessings be upon him) said: "The slaughter of a hide is its tanning."
Hadith Referenceالمعجم الكبير للطبراني / باب السين / 6311