Iʿtikāf of the Month of Ramaḍān In the Cave of ḤIRā’

It was the blessed practice of the Leader of Both Worlds  long
before prophethood, to seek the seclusion of the Cave of Ḥirā’ for worship.
He used to go there at different times of the year. In addition to this, the
Noble Prophet’s  blessed practice during the month of Ramaḍān
was quite unique, regarding which, Ibn Shihāb al-Zuhrī  and Qatāda 
state:
بعث النبی صلی الله علیه وسلم یوم الاثنین من رمضان
The Prophet  was blessed with prophethood on a Monday in
the month of Ramaḍān.
We usually hear, regarding the advent of prophethood, that the Prophet
 was blessed with prophethood on a Monday in the month of Rabīʿ
al-Awwal. However, Ibn Shihāb al-Zuhrī  and Qatāda  have differed from
this general opinion by maintaining the view that the process of revelation
of the Qur’ān to the Prophet  began on a Monday in Ramaḍān. It
was during this regular seclusion in the blessed month of Ramaḍān that
the process of revelation of the Qur’ān began. It is for this reason that the
above mentioned scholars have said,
بعث النبی صلی الله علیه وسلم یوم الاثنین من رمضان وکان رسول الله صلی الله علیه
وسلم یتعبد فی غار حراء فی رمضان
The Prophet  was blessed with prophethood on a Monday in
the month of Ramaḍān, and the Prophet  used to worship in
the Cave of Ḥirā’ in the month of Ramaḍān.
The Arabic word used in the Ḥadīth is “کان” (“Kāna”).
indicating that it was a long-established ”کان رسول الله صلی الله علیه وسلم یتعبد“
habit of the Noble Prophet  that “he used to” regularly go to the
Cave of Ḥirā’ for worship during Ramaḍān.