Say: “My Lord has forbidden all indecencies whether open or secret, sin and rebellion against justice, committing shirk with Allah for which He has granted no sanction, and saying things about Allah of which you have no knowledge.
Meaning:-
Forbidden : refuse to allow (something), prohibit, not allowed, banned.
Rebellion: disobedience, insubordination,
shirk (Arabic) : is the sin of practicing idolatry or polytheism, i.e. the deification or worship of anyone or anything other than the singular God i.e. Allah. Literally, it means ascribing or the establishment of “partners” placed beside God.
sanction: official permission or approval for an action.