We must stop and ask God to search and know our hearts—a call to humility and examining our motives. Our beating heart is the organ that takes the oxygen we breathe into our lungs, then pumps oxygen-rich blood through the body. God breathed life into us at creation. Our beating heart sustains that breath of life. It's no coincidence that the heart is used metaphorically throughout scripture. If our hearts are corrupt with things that are not of God, it will slowly suffocate us. God wants us to allow him to see our hearts and examine them. The Holy Spirit can then lead us to conviction of anything that needs to be dealt with. We don't want any clogged arteries around here. 
 
Search me, God, and know my heart;
    test me and know my anxious thoughts.
See if there is any offensive way in me,
    and lead me in the way everlasting.
Psalm 139:23-24