Hazrat Mufti Ebrahim Salejee (Daamat Barakaatuhu) mentioned:
The oyster waits with its mouth open. When a raindrop gets into it, after some time it becomes a pearl. In the similar manner we need to constantly focus towards Allah Ta‘ala. Our attention, concern and concentration needs to be towards Him in all conditions. There must be a constant cry. During our private time or when we are driving alone, we should be crying from our hearts and engaging in zikr. We never know which zikr will be accepted and when that lucky moment may come and His grace may engulf us.