(9) The heart is deceitful above all things and beyond cure. Who can understand it?
(10) “I the Lord search the heart and examine the mind,
to reward each person according to their conduct,
according to what their deeds deserve.”
How can I trust my own heart? The answer is "I can't!" So for me it boils down to seeking the one who's heart is perfect; the one who's desires are perfect. The spirit of Christ dwelling in my heart allows me to move toward a pure heart; because HIS heart is pure.
Jeremiah provides this encouragement before his warning (verses 7-8):
(7) “But blessed is the one who trusts in the Lord, whose confidence is in him.Trust in God today and not in our own desires. His ways are higher than ours. His thoughts are higher than ours.
(8) They will be like a tree planted by the water that sends out its roots by the stream.
It does not fear when heat comes; its leaves are always green.
It has no worries in a year of drought and never fails to bear fruit.
Prayer for my friends: Lord, this week, may your desires be our desires; may your thought be our thoughts. Search us Lord and change our hearts. We long to trust you. Plant our feet firmly next to your streams of living water and help us not to fear during difficult times.