Ad-Dhikr is Qur'an as 'ummul-kitab' is to

The term "ummul-kitab" in the Quran is used to refer to Surah Al-Fatihah, which is considered the mother of the Quran, containing the essence of the entire scripture. Similarly, Ad-Dhikr refers to the remembrance of Allah, which is considered the essence of the Quran and the core of Islamic worship. Ad-Dhikr is the act of reciting and reflecting on Allah's names and attributes, as well as his commands and promises, with the aim of increasing one's faith, devotion, and mindfulness of Allah in all aspects of life. Just as Al-Fatihah is recited in every prayer and is essential for the validity of the prayer, Ad-Dhikr is also an integral part of Islamic worship, recommended and encouraged by the Prophet Muhammad (peace be upon him) as a means of attaining Allah's pleasure and protection.