Which book of the Bible is often referenced to support the teaching of milk principles?

The book of Hebrews is often referenced to support the teaching of milk principles because it discusses foundational aspects of the faith and encourages the readers to move beyond the basics towards maturity in understanding. In Hebrews 5:12-14, the author highlights the difference between those who are still in need of milk (symbolizing basic teachings) and those who are ready for solid food (representing deeper theological insights). This concept is crucial for teaching the early principles of faith, as it emphasizes the importance of growing in spiritual understanding and moving towards a more profound relationship with God.

This makes Hebrews a central text in the context of the milk principles, as it explicitly addresses the necessity of foundational teachings for spiritual growth and maturity.