פירוש על עבודה זרה 74:6

This is the first attempt to resolve the difficulty. According to the Torah only one who comes into contact with a dead body is defiled. One who comes into contact with such a person is not defiled. The rabbis added that he too is defiled, but then Yose b. Yoezer came and restored the law to the more lenient, biblical law. That is why they called him a “permitter.”