What does the Bible say about spiritual mysteries?

In Scripture, a spiritual mystery is a truth that transcends human comprehension and requires divine revelation for understanding. Ephesians 3:3-6 illustrates this, where the Apostle Paul discusses the mystery of Christ and the inclusion of Gentiles as fellow heirs in the body of Christ. Understanding such mysteries is not attainable through natural reasoning; instead, it is the Holy Spirit who unveils these truths to the faithful. Hence, biblical mystery is not like a suspense novel but a divine revelation known only to God's elect.