Col 2:17, Heb 8:5, 10:1

God commanded the Israelites to observe three feasts. (Ex 23:14)

Ex 23:14 Three times thou shalt keep a feast unto me in the year.

The three feasts that God commanded to be observed were to explain the coming Christ. (Col 2:17)

Col 2:17 Which are a shadow of things to come; but the body is of Christ.

The tabernacle is also to explain the true tabernacle, Christ. (Hebrews 8:5)

Hebrews 8:5 Who serve unto the example and shadow of heavenly things, as Moses was admonished of God when he was about to make the tabernacle: for, See, saith he, that thou make all things according to the pattern shewed to thee in the mount.

The sacrificial laws of the Old Testament also explain the coming Christ. (Heb 10:1)

Heb 10:1 For the law having a shadow of good things to come, and not the very image of the things, can never with those sacrifices which they offered year by year continually make the comers thereunto perfect.