Some people might wonder why it matters whether a person keeps a Saturday Sabbath or not. Why even bother learning about the Sabbath, the holy days, and other Old Testament commandments? The fact is, most people who believe in these old commandments believe they have received revelation from God to keep them. They see them as something all believers must keep. Therefore, they feel compelled to convert as many Christians as possible to their own beliefs, causing confusion and focusing on the wrong people to reach. Knowledge is a wonderful thing to have. And it is a good defense against error. Having a well-balanced understanding of biblical teachings can help us personally and help us to help others, keeping them from falling into error. The powerful information written in this book is a defense of the truth, a shield against er- ror, and a helmet against confusion, helping the believer to stand firm with confidence when those of error come at them or people they care for. Knowing the power of the work of Christ in fulfillment can strengthen the believer and assure that the spirit of confusion cannot penetrate their mind while also empowering them to give answers when needed.