Jabir said he heard God’s Messenger say in the year of the Conquest when he was in Mecca, "God and His Messenger have declared forbidden the sale of wine, animals which have died a natural death, swine and idols.” He was asked what he thought of the fat of animals which had died a natural death, for it was used for caulking ships, greasing skins, and making oil for lamps, and after saying that it was unlawful he added, "God curse the Jews! When He declared the fat of such animals unlawful they melted it, then sold it and enjoyed the price they received. “ (Bukhari and Muslim.)