أَفَرَأَيْتُمُ اللَّاتَ وَالْعُزَّى
وَمَنَاةَ الثَّالِثَةَ الْأُخْرَى
أَلَكُمُ الذَّكَرُ وَلَهُ الْأُنثَى
تِلْكَ إِذًا قِسْمَةٌ ضِيزَى. سورة النجم - سورة ‏٥٣: ١٩-٢٢‏
Sura an-Najm 53:19-22 are related to the time when Muhammad spoke the the Satanic Verses.
In Sura Hajj 22:52-53, Muhammad confessed his mistake, alleging that all prophets were tempted by Satan who inspire them with demonic verses, as if they were actually revealed by God. But later on Allah abrogated those Satanic Verses with new revelations and instructs his prophets with new verses. According to Islam, Allah permits such demonic inspiration to test weak believers and to cut off those with hardened hearts.
The true, vital issue about the Satanic verses is this. If Muhammad were unable to distinguish Satan's voice from God's voice, then could there be verses in the Qur'an that Muhammad assumed were from God but were really from Satan? Maybe much of the Qur'an is Satanic in origin, in spite of Muhammad's conviction that it was entirely from Allah.
The Qur'an clearly states that Muhammad spoke in the name of God and that he said things that God had not commanded him! Next, he charges that all the prophets of God voiced Satanic statements! According to the holy law of God, Muhammad ought to have been put to death as a false prophet! According to the Holy Scriptures, if a prophet spoke anything in the name of LORD that was not from Him, the prophet must be put to death! Muhammad spoke in the name of Allah and then admitted that he had really spoken the words of Satan.
Oops!