Numbers 1-3:32

Numbers is the fourth book of the Pentateuch.  It describes the 38 years covering the end of the encampment at Mt. Sinai through the journey in the desert to their arrival at the border of  the Promised Land. It begins with a census of the Chosen People commands by the Lord. Thus, the journey of the law, from Sinai to the Promised Land begins with a census. Similarly, the story of the birth of the New Law, the fulfillment of the law, Jesus Christ, also begins with a census.  The census ordered by the Romans is the reason Joseph and Mary journeyed to Bethlehem, of course.