Quran 57:8 — Iron (Al-Hadeed)

وَما لَكُم لا تُؤمِنونَ بِاللَّهِ ۙ وَالرَّسولُ يَدعوكُم لِتُؤمِنوا بِرَبِّكُم وَقَد أَخَذَ ميثٰقَكُم إِن كُنتُم مُؤمِنينَ

Why should you not believe in GOD when the messenger is inviting you to believe in your Lord? He has taken a pledge from you, if you are believers.

[57:7] Believe in GOD and His messenger, and give from what He has bestowed upon you. Those among you who believe and give (to charity) have deserved a great recompense.

[57:9] He is the One who sends down to His servant clear revelations, in order to lead you out of the darkness into the light. GOD is Compassionate towards you, Most Merciful.