Dates were set in ancient Israel by the month, not the week. The months were numbered. In neighboring countries the months and the days had names, the names of various gods. By referring to days and months simply by numbers, Israel, however, sought to avoid this polytheistic practice of deifying the movement of time. Nevertheless, after their contact with the Babylonians they began to refer to the months by names. In this calendar the numbering of the months begins in the spring.