This is an Acknowledgment for mankind to warn them and to make them know that indeed their Deity is the Only Deity, and to remind the one endowed with the intelligence.
The Truth and Proof Adhikr is revealed upon 313 Messengers to warn mankind that there is no deity except Allah and to serve Him alone as explained in verse 4: 163. Messenger’s people must introduce to other people belonging to Messenger’s community that they have no protectors and interceders besides Lord. But the Arabic Quran reading Fujjar by hiding and rejecting Adhikr are teaching and learning Fujjar Books.
The believer who testifies Adhikr changes his Jinn soul mate into a believer and keeps Lord in his heart as explained in verses 2: 152 and 3: 190-191. They are those who endowed with intelligence as told in this verse. See explanation 2: 25, 119, 282 and 9: 71-72.