How do we know that Christ's words sanctify us?

The sanctifying power of Christ's words is encapsulated in John 15:3, where He reiterates, 'Now ye are clean through the word which I have spoken unto you.' This indicates that His teachings and proclamations have a profound effect on our spiritual condition. In conjunction with the work of the Holy Spirit, the gospel message serves as the instrument through which believers are cleansed and set apart for the Lord's purpose. The cleansing and sanctification processes happen in the believer's heart as they remain in Him and abide in His teachings, leading to spiritual growth and fruitfulness.