2000 years before christ

IF I am correct, that is about the time Moses introduced GOD'S laws, AKA "The Law Of Moses", to the children of Israel.  A large part of worship was the act of living out these laws every day.  These were GOD'S laws which means they were Holy and to be treated as such.  These were so important, that Moses told them to write them down and make them visible to their eyes, so they may see them daily! There were also the matters of the gathering of the comgregation of the tabernacle.  Like today, they read GOD'S word and prayed.  Unlike today, they offered sacrificial animals for various reasons, mostly sin.  These laws are in the book of Leviticus.  Other religions involved similar practices, bowing, praying, and sacrificing to a different god or multiple gods, sometimes trading animal sacrifices for human sacrifices.  This is about the best I can do for you, as I didn't live in that day.  Hope it was some form of help.  To sum it all up, worship is a way of life that is continually right in GOD'S eyes.  Thats the way it was meant to be then, and now,only, without killing all those innocent animals.  Thanks to Jesus for His sacrifice, My sacrifice is one of praise, and the giving of my "self" for His will and purpose.

This is the time of the early days of Moses and his experience with the so called "burning bush" when he heard the voice of God and felt the call to help the Israelits who were in bitter slavery. Worship was a matter of obedience and action  and Moses acted to lead the children of Israel out of slavery. This setting is in Exodus. They also sang praises to God and danced and rejoiced in God. After crossing the Red Sea they erected  a stone monument. They carried the ark of the covenant with them for many years which was their symbol of God's presence among them.

This was a tent which contained sacred item such as the commandments.This being after Moses came down from the mountain with the two tablets of stone which contained the ten commandments--the seconds copy after he broke the first set. So law and obedience was very imporatant. Leviticus tells of the sacrifice of animals which was ritualized a bit later as has been described in the previous answer. The first blood sacrifice,however, was the last of the plagues as they then left Egypt. A lamb was slain and the blood put on the lintel and door post so that the first born in the Israel homes would not die as the death angel passeed over. The Egyptians who did not bellieve Moses  words would not  do this and there was mourning all across Egypt.

You might find it interesting to know that orthodox Jews still sacrifice animals just like it happened in Old Testament times.