No one builds a house without a blueprint. Neither did God create the universe without a plan.
There are three events that are the pillars of all creation. The universe hangs on these three events and the future of every man is connected to them. These three things are the death of Jesus Christ, the resurrection of Jesus Christ, and His return to the Earth to reign as King of Kings and Lord of Lords.
God revealed this blueprint to His people through the annual Holy Days and that is why the Church of God celebrates them beginning with Passover and the Days of Unleavened Bread.