What is the nature of the human heart, and how does God relate to it?

The heart of man is deceitful and desperately sick, being more deceitful than all else. It is incurable and malignant, meaning that without faith, the mind is under the dictates of the sin nature and absolutely cannot be trusted. The Hebrew word aqob describes the heart as deceitful, fraudulent, and polluted. No one can understand the heart except God, who alone knows our real inner workings. Through His searching and testing, God evaluates thoughts and motives to give to each person according to their ways and the results of their deeds. He wants us to know what is on the inside and who is in control there, but we will never truly understand ourselves until God brings it out. This process involves putting us in various situations to apply what we know, and all the while, God evaluates our inner workings (Heb. 4:13). The ultimate purpose of God's searching and testing is to give to each of us according to our ways, according to the results of our deeds. Only what is produced by the Spirit of God through us is acceptable to Him, as the Lord Jesus Christ taught that there are two kinds of life: physical and spiritual (John 3:6).