Jesus here quotes from Isaiah 29:13 in charging the religious leaders of His day with setting aside God’s Word by their traditions. Jesus dismisses their worship because their hearts were not aligned with their lips. Living faith—true worship—requires that the mouth and the heart be together in a unity that prevents any tinge of hypocrisy.
Praises and true faith emanate from lips that draw from the depths of the heart. When speaking in faith flows as a living principle, the words are not a ritual recitation of slogans; such recitation is only acting out a human tradition and, as Jesus indicates, is potentially hypocritical.
Just as we are called to genuine praise and worship, not as pretenders or ritual performers, so let our confessing of God’s promises be without hypocrisy. Let us speak what God’s Holy Spirit has truly birthed in our hearts, thereby causing us to speak faithfully with our lips.
Has God dropped a promise into your heart? Then speak it forth with the courage of convinced faith and watch Him who gave you the word fulfill it.