Then you shall bring Aaron and his sons to the entrance of the tent of meeting and shall wash them with water and put on Aaron the holy garments. And you shall anoint him and consecrate him, that he may serve me as priest.
The book of Exodus begins with the children of Israel suffering in slavery in Egypt seemingly forgotten by God. It ends with the glory of God filling the Tabernacle and Aaron and his sons beginning the ministry of the priesthood as all of Israel joins in covenantal worship of God. The journey that the Lord took them to in order to get them to this point was a lesson in leadership for Moses, and submission to God for the nation. And we find points of identity along the way.
Like newly freed slaves unsure of anything, we are insecure in life outside of what we once knew. We forget the pains of our past slavery to sin when we long for the food of our slave days. Even as God supplies for us, we may forget He is doing that. We may grumble against His leadership. We may turn to idols we have made rather than follow His Word. But in it all, God remains sovereign, loving, corrective, and amazing. It always astounds me when reading Exodus that as much as Israel fearfully grumbled and wavered in faith, God patiently kept providing for their every need, both in Egypt and in the desert.
And it all led to worship. That is how the book ends. The priests are anointed and clothed in holy garments. The tabernacle and its furnishings are prepared and engaged in the worship practices. God is front and center in Israel's camp and as they follow His Law, His glory fills their worship in the Tent of Meeting. It took the miracle of the plagues, the crossing of the Red Sea, the drowning of Egypt's army, the giving of the Law, several failures including the golden calf debacle, and the appointment of the Aaronic priesthood to get them there. But in the end they worshiped.