The tabernacle was erected on the first day of the first month of the second year (v. 17). The first month of the first year was the time of the passover (Exo. 13:4). Hence, the time from the passover to the erecting of the tabernacle was one year.
God’s people had two beginnings, the first at the passover, which was for their salvation, and the second at the erecting of the tabernacle, which was related to the building of God’s dwelling place. Every genuine Christian should have these two beginnings: the experience of salvation and the practical experience of the building of the church as God’s dwelling place (1 Tim. 3:15).