Your Heart
You cannot change your heart, you cannot of yourself give to God its affections; but you can choose to serve Him. The heart is deceitful above all things, and desperately wicked;Who can know it?(Jer.17:9) You can give Him your will; He will then work in you to will and to do according to His good pleasure.(Phil.2:13) Thus your whole nature will be brought under the control of the Spirit of Christ; your affections will be centered upon Him, your thoughts will be in harmony with Him. SC 47.1