Those who have said “Our Lord is Allāh” are many, but..
Allāh (ﷻ) said:
إن الذين قالوا ربنا الله ثم استقاموا
❛Indeed, those who have said, "Our Lord is Allāh" and then remained on a right course..❜ [Fussilat, 30]
Ibn Rajab al-Hanbalī (رحمه الله) has commented on the verse:
الذين قالوا ربنا الله كثير ، ولكن أهل الاستقامة قليل
❛Those who have said "Our Lord is Allāh" are many; yet the people of righteousness (i.e. those who remained on the right course) are few.❜
[Majmū’ Rasāil, 1/339]
