أفمن شرح الله صدره لﻼسﻼم فهو على نور من ربه
Is he whose breast Allah has opened to Islam, so that he is in light from his Lord,
means, is this person equal to the one who is hard-hearted and far from the truth?
This is like the Ayah:
أومن كان ميتا فٲحيينه وجعلنا له نورا يمشي به فى الناس كمن مثله في الظلمت ليس بخارج منها كذلك
Is he who was dead and We gave him life and set for him a light (i.e. Belief) whereby he can walk amongst men -- like him who is in the darkness (i.e., disbelief) from which he can never come out. (6:122)
Allah says:
فويل للقاسية قلوبهم من ذكر الله
So, woe to those whose hearts are hardened against remembrance of Allah!
meaning, they do not become soft when Allah is mentioned, and they do not feel humility or fear, and they do not understand.
أوليك في ضﻼل مبين
They are in plain error!