So know that the heart is a polished mirror – all of it is a face – that does not (itself) ever “rust”. So if someone should say about it that it rusts – as in the (Prophet’s) saying: “Certainly hearts tarnish like iron,” in the hadith that concludes “the polishing of the heart is through remembrance of God and recitation of the Qur’an…” – that is because the heart has become preoccupied with knowing the secondary causes (al-asbab), the apparent workings of this world, instead of with knowing God. So its attachement to what is other than God has “rusted over” the face of the heart, in that it blocks the self-manifestation (tajalli) of the Truly Real in that heart.
For the Divine presence is perpetually manifesting Itself, and one could never imagine Its ever veiling Itself from us. So when this heart fails to receive that (divine Self-manifestation) from the direction of the praiseworthy and relevatory divine addressing (speaking to us), because it has received something else instead, then its act of receiving that something other (than God) is what is referred to (in the scriptures) as “tarnishing”, “veils”, “locking”, “blindness”, “rust” and the like. For in fact the Truly Real Himself is (perpetually) bestowing this knowing on you in the heart, except that (your heart) is (preoccupied with) knowing something other than God – although the Knowers of-and-through-God know that in reality (that distracted heart) too is actually knowing of and through God.
Excerpt from Ibn ‘Arabi’s “The Reflective Heart” chapter 2 (II, 82-83)