The Spoils of War - 8:2
Those who believe are such that their hearts tremble when Allah is mentioned, and their faith increases when His verses are recited to them, and they trust in their Lord.
Related:
The Companies/39:23
Allah has sent down the best hadith in a coherent book in two parts. The skins of those who honor their Lord tremble because of it. Then their skins and hearts soften towards the message of Allah. This is Allah´s guidance; He guides whom He wills and/or guides whom He wills to it. There is no guidance for anyone whom Allah leads astray
The Repentance/9:124
"Whenever a surah comes down, there are those who ask, "Which of you has this surah increased your faith?"Indeed it has increased the faith of the believers, and they rejoice and give glad tidings to one another."
The Pilgrimage/22:35
They are such that their hearts tremble at the mention of Allah. They are patient in what befalls them, they observe the prayer and spend out of what We have provided them for charity.
The Light/24:51
"When they are called to Allah and His messenger to judge between them, the believers say only this: "We have heard and obeyed."These are the winners."