Jeremiah 24:7
And I will give them an heart to know me, that I am the LORD: and they shall be my people, and I will be their God: for they shall return unto me with their whole heart. And I will give them an heart to know me, that I am the LORD: and they shall be my people, and I will be their God: for they shall return unto me with their whole heart.
God Himself gives people a heart and mind to know and understand that He is the Lord. To know Him in this sense means to have a true conception of His character. This knowing is personal acquaintance with Him that brings peace and good, coming through receiving the law from His mouth and laying up His words in the heart. Satan seeks to obscure that true knowledge by misrepresenting God.
From the beginning his studied plan has been to cause people to forget God and to secure them to himself by depicting God as arbitrary, severe and unforgiving, clothed with the attributes of the prince of evil itself. By that misrepresentation he leads them to fear, shun and even hate Him, to put Him out of their thoughts, to lose the divine image, to take on his own likeness and spirit, and to become captives to his will. Even the covenant people, chosen to preserve that knowledge in the world, had lost the true knowledge of God.
Jesus reveals the character that God wants His people to display. In connection with this promise, God pledges to increase His grace. The verse promises that they shall return to Him with their whole heart. It calls those who have backslidden to make that wholehearted return without delay.