What You Should Know About the Passover and Festival of Unleavened Bread (hwalibrary.com)
CREATION is the proof of the existence of God. Creation identifies God. The Sabbath is a weekly memorial of creation. A weekly reminder of God's power to create. Therefore it identifies God to us - keeps us in the true memory and true worship of the true God. No other day but the SEVENTH DAY OF THE WEEK could have that great significance and MEANING. It was designed to keep us in the true worship of God. The purpose of Holy Days. Now in like manner, God gave His Church seven annual Sabbaths. These Holy Days were given to keep God's children in the true memory and worship of God by keeping us constantly in the understanding of God's great plan of redemption.