I think that Jacob, as the temple priest, may have been concerned about blood coming on to his own garments. Where would a temple priest encounter blood? Every time he sacrificed an animal, he would likely get stained in blood. That blood, of course, was atoning blood and was expiating for the sins of the people who were making the sacrifices. The priest was a holy person who could absorb that blood, whereas the other people could not. The priest would go through his own re-purification so that he could serve as a holy instrument ensuring that his people’s sins would be forgiven. He would also light a fire and keep it burning continually on the altar of the temple, day and night, according to Leviticus 6:12–13. They continually kept a fire burning so that the impurities could be put into the fire and burned. Thus, when Jacob referred to the branches that were being cut off, "hewn down and cast into the fire," he may have also been referencing some of the things he did for them as their temple priest.