Translation:

70. Knowest thou not that Allah knows all that is in heaven and on earth? Indeed it is all in a record and that is easy for Allah.

Notes (Tafseer)

2851. We human beings can only think of knowledge being accurately and permanently preserved by means of a record. Allah's knowledge has all the qualities of a perfect record, and it is moreover complete and comprehensive. This is not difficult for Him from whom flow all knowledge and intelligence.