Understanding the Significance of Psalm 66:18 in Our Spiritual Lives

What Does Psalm 66:18 Mean:

“If I regard wickedness in my heart, The Lord will not hear”

To "cherish" sin in the heart could also mean "to intend" to sin. For example, Jesus said, "but I say to you that everyone who looks at a woman with lust for her has already committed adultery with her in his heart" (Matt. 5:28). Such a person plans and looks for the opportunity to commit the sin. That's what King David did (2 Sam. 11). 

As long as the intent to sin was rooted in his heart, his prayers would have been in vain. 

Therefore, my constant prayer to God is, "keep back Your servant (me) from presumptuous sins; Let them not rule over me; Then I will be blameless, And I shall be acquitted of great transgression. Let the words of my mouth and the meditation of my heart Be acceptable in Your sight, O LORD, my rock and my Redeemer" (Psalm 19:13-14). Amen.

Blessings!