The Heart Is King

“But I have a good heart”…

Ibn Taymiyah said:
القلب هو الملك، والأعضاء جنوده
“The heart is king and the limbs are its obedient soldiers.”
[“Majmu al-Fatawa”, 2/6].

The fact that our hearts command our limbs to perform bad deeds and no good deeds, means that our hearts are not clean.

They say:
آنچه در دیگ است در کاسه می برآید
“Whatever is in the pan will come out in the bowl.”

That is the meaning of the Prophetic statement:
أَلاَ وَإِنَّ فِي الْجَسَدِ مُضْغَةً إِذَا صَلَحَتْ صَلَحَ الْجَسَدُ كُلُّهُ، وَإِذَا فَسَدَتْ فَسَدَ الْجَسَدُ كُلُّهُ‏.‏ أَلاَ وَهِيَ الْقَلْبُ ‏
“Beware! There is a piece of flesh in the body if it becomes good (reformed) the whole body becomes good but if it gets spoilt the whole body gets spoilt and that is the heart.”
[“Sahih Bukhari”, 52].
https://sunnah.com/bukhari:52

And both the internal and external are important…if someone scratches your car, you don’t say: “It doesn’t matter, the internal engine is fine.”