Second Temple Judaism was centered not on synagogues, which began to appear only in the 3rd century BCE, and the reading and study of scripture, but on the Temple itself, and on a cycle of continual blood sacrifice (meaning the sacrifice of live animals). Torah, or ritual law, was also important, and the Temple priests were responsible for teaching it, but the concept of scripture developed only slowly. While the written Torah (the Pentateuch) and the Prophets were accepted as authoritative by the 1st century CE, beyond this core the different Jewish groups continued to accept different groups of books as authoritative.