surely allah does not forgive that a partner be ascribed to him although he forgives any other sins for whomever he wills. he who associates anyone with allah in his divinity has indeed forged a mighty lie and committed an awesome sin.
إن الله لا يغفر أن يشرك به ويغفر ما دون ذلك لمن يشاء ومن يشرك بالله فقد افترى إثما عظيما