Good cases have been made for both exilic and post-exilic composition, leading to the conclusion that it has at least two layers, spanning a broad time period of 571–486 BCE. This was a period when the careful observance of ritual was one of the few means available which could preserve the identity of the people, and the narrative of the priestly authors created an essentially stable and secure world in which Israel's history was under God's control, so that even when Israel alienated itself from God, leading to the destruction of Jerusalem and the exile in Babylon, atonement could still be made through sacrifice and ritual.