Answer: Enjoining good: means enjoining people to do every act of obedience to Allah Almighty, and forbidding evil: means forbidding people from every sin with which they disobey Allah Almighty.

Allah Almighty says: {You are the best nation ever raised for mankind: you enjoin what is right and forbid what is wrong, and believe in Allah.} [Surat Āl ‘Imrān: 110]