Oh my dear son! You establish prayer, and enjoin the doing of what is right and forbid the doing of what is wrong; and be patient whatever affects you for that, indeed it is from the confirmed determination of affairs.
Prayer is commanded to keep up Book Dhikree (Adhikr) as explained in verse 20: 14. Since there is no group of believers anywhere in the word, the odd believer should follow prayer and lifestyle as explained in verses 7: 205-206. Right is the way of the Lord while wrong is the way of Satan. Right is from the Lord and wrong is from Satan as explained in verse 4: 79. Adhikr is the only Criterion to distinguish good and evil. So it is commanded to convey Adhikr to the entire mankind for enabling mankind to distinguish right and wrong. Conveying Adhikr is serving and helping the Lord so that the Lord will help him back as explained in verse 22: 40. See explanation 5: 67; 9: 67-68, and 15: 94-95.