First Mention of Worship
The first mention of any significant truth in the Scriptures acts a a reference point for all future mentions, this being one of the basic principles of Bible interpretation (Hermeneutics).
The first mention of worship is found the very first book of the Bible in Genesis 22:5. Abraham is about to take Isaac and sacrifice him in direct obedience to God. I know it sounds odd but please stay with me here.
Abraham says to his servants, "Stay here with the donkey while I and the boy go over there. We will worship and then we will come back to you". So what is going on here? No mention of any singing. There is no band with instruments! No song sheets or hymn books. It is simply that Abraham was obeying God.
Please note what Abraham said, "We will worship and then we will come back to you". How could he say "we will come back"? He could say it because the Lord had previously promised Abraham that Isaac's descendants would become a great nation (see Genesis 17:19). That clearly would not be the case if Abraham was to kill Isaac!
Abraham's faith had taught him that whatever God told him to do, His Word could never be violated, and even if he had to go through with the sacrifice of Isaac, God would raise him from death back to life in order that His Word would be fulfilled.
What Abraham demonstrates is:
Faith expressed in Obedience
In other words, Worship!