It is true, that the heart is deceitful above all things, and desperately wicked. But it does not negate the fact that the heart should love God through faith. For the heart represents our love. Thus, if God has our hearts, then He has our love. The intimacy of knowing God’s love within the depths of the heart enables the heart to freely love God; because of who He is. This is immensely deeper, and goes infinitely beyond. Due to the love of God surpassing all knowledge and understanding. For that reason, an intellectual knowledge of God’s love will never suffice the heart. If it is not known personally.
Love itself is personal. And must be experienced on a personal level. If the heart is in rebellion against God because of sin, not knowing His love, then just to have an intellectual knowledge of it becomes a mere perspective, and not a perspective that is held with significant value. This could lead to forcing the heart in submission to what it hates. Suppressing the sinful tendencies of the sinful nature, in order to live righteously in obedience. Without actually having a genuine love for God from the heart, the heart will eventually grow weary, and tired. Seeing God as a heavy burden to believe in. Either to inevitably capitulate, living a double life of sin or the renunciation of what it hates to live for the sin it loves. Hence, hypocrisy, and the renunciation of belief in God.
This is not to imply we must live by impulse (feeling) alone. For the problem is, we could know what is right and do the opposite because of impulse. Impulses has to rationally be held accountable to the truth. Not to do whatever which is pleasing contrary to it, satisfying the works of the flesh. It is not faith based on pure impulse or reason, but a sense of knowing God’s love to be true according to His word.
In conclusion: we should all individually know in our hearts God’s love for us. We should know personally that Christ died for us. If some of us do not, while living pretentiously, we put ourselves endanger of being self deceived. God wants reconciliation. Reconciliation means we are made right through faith in Jesus Christ. Receiving the spirit of adoption. Where we know that we are right with God. Knowing we belong to God because of His love for us. In this we can have peace, confidence and absolute boldness.