How do we know the Holy Spirit's teaching is true?

The truth of the Holy Spirit's teaching is demonstrated through His work of illuminating Scripture and revealing Christ to us. John 16:13 indicates that the Spirit guides us into all truth, providing clarity and understanding that surpasses mere intellectual knowledge. This illumination is evidenced by a believer's transformation, as they come to see their sin and their Savior in a new light. The Spirit's work is not only about understanding doctrinal truths but also about experiencing the power and sweetness of these truths in our lives.