When the bible talks about your heart it is not talking about your physical blood pumping organ. it is talking about your spirit or inner man. Your spirit needs nourishment, light and exercise much like your physical body does. To ignore or neglect the condition of your inner man is the same as planning to fail. Neglect is enough to bring ruin.
Most Christians don’t understand this. When hard choices arise, having a strong inner man makes the decisions easier and the direction clear. The strength of your inner man has a direct impact on your ability handle the difficult things that life throws at you, as well as having an impact on your physical body.
Proverbs 18:14 ~ The strong spirit of a man sustains him in bodily pain or trouble, but a weak and broken spirit who can raise up or bear? (Amp)
Your first ministry is your own spiritual progress. If your spirit is weak and underdeveloped, it will hinder your growth and progress as well as your ability to minister to the needs of others.
Feed on God’s word, worship Him and pray. Fellowship with other believers and endeavor to obey and live out the word of God that you know. This will bring you strength.
Stay away from things that you know make you weak. Avoid exposure to old habits and temptations that pull on your flesh. Your heart is the vessel that the life of God flows through, keep it healthy.
Proverbs 4:23 ~ Keep your heart with all diligence, For out of it spring the issues of life.