How do we know our hearts can deceive us in worship?

In Mark 7, Jesus teaches that it's not what enters a person that defiles them, but what comes out from their heart. This indicates a profound truth: our inward condition affects our relationship with God. The heart can lead to hypocrisy, as it may outwardly conform to rituals while remaining far from genuine devotion. Understanding this nature of the heart is crucial for Christians, as it compels us to ensure that our worship is rooted in sincerity and truth, not merely in external actions or traditionalism.