How intense must the fear of Allah of a sincere believer be?

Everyone who is aware of the being of Allah and who knows Him with His supreme attributes fears Allah deeply. This is because in addition to being infinitely compassionate and merciful, Allah is also al-Qahhar (the Subduer), al-Hasib (the Reckoner), al-Muazzib (the Punisher), al-Muntaqim (the Avenger), al-Saiq (the One Who consigns to Hell). Therefore, Muslims fear Allah in the unseen; they know no one is safe from His punishment. Since they know that they will be accountable for everything they do, they greatly avoid behaving in any way displeasing to Allah. However, it must be added that fear, as referred to here, has a totally different connotation from the typical fear felt in irreligious societies. It is a fear that gives peace to the believer, motivates him and prods him to action to gain Allah’s approval. Allah commanded the believers as follows:

So fear Allah as much as you can, and listen and obey and spend in charity for the benefit of your own soul. It is the people who are safeguarded from the avarice of their own selves who are successful. (Surat at-Taghabun, 16)

How intense must the fear of Allah of a sincere believer be?