Gleanings — Paragraph 304
Source (Arabic)
(سوره وفا) وأمّا ما سألتَ من العوالم، فاعلم بأنّ لله عوالم لا نهاية بما لا نهاية لها وما أحاط بها أحد إلّا نفسه العليم الحكيم
Translation
As to thy question concerning the worlds of God. Know thou of a truth that the worlds of God are countless in their number, and infinite in their range. None can reckon or comprehend them except God, the All-Knowing, the All-Wise.