I wholeheartedly know and understand that Allah (swt) cannot be seen nor is he comparable to anything. But sometimes when I do Dhikr of Allah (swt) an image comes in my head. How do I remove this and stop images in my mind?
Bismillah
Thank you for your question. While God cannot be compared with His creation, His creation manifests His perfection. To try to completely empty the mind and heart is a nigh impossible task as humans are limited beings and even their conception of emptiness or limitlessness is faulty. There is no harm in images as long as they are not the subject of your worship.
May you always be successful