The Idolators' Accusation that the Prophet was a Liar since some Ayat were abrogated, and the Refutation of their Claim
Allah tells us of the weak minds of the idolators, and their lack of faith and conviction. He explains that it is impossible for them to have faith when He has decreed that they are doomed. When they saw that some rulings had been changed by being abrogated, they said to the Messenger of Allah ﷺ:
إِنَّمَآ أَنتَ مُفْتَرٍ
(You are but a forger) meaning one who tells lies. But Allah is the Lord Who does whatever He wills, and rules as He wants.
بَدَّلْنَآ ءَايَةً مَّكَانَ ءَايَةٍ
(And when We change a verse (of the Qur'an) in place of another) Mujahid said: this means, "We remove one and put another in its place." Qatadah said: this is like the Ayah:
مَا نَنسَخْ مِنْ ءَايَةٍ أَوْ نُنسِهَا
(Whatever verse We change abrogate or omit the abrogated...)" (2:106). Allah said, in response to them:
قُلْ نَزَّلَهُ رُوحُ الْقُدُسِ
(Say: "Ruh-ul-Qudus has brought it...") meaning, Jibril,
مِّن رَّبِّكَ بِالْحَقِّ
(from your Lord with truth, ) meaning, with truthfulness and justice
لِيُثَبِّتَ الَّذِينَ ءَامَنُواْ
(for the conviction of those who believe,) so that they will believe what was revealed earlier and what was revealed later, and humble themselves towards Allah.
وَهُدًى وَبُشْرَى لِلْمُسْلِمِينَ
(and as a guide and good news for the Muslims.) meaning He has made it a guide and good news to the Muslims who believe in Allah and His Messengers.
Sequence of Verses
In the previous verse (98), there was an instruction to say اَعُوذ بِاللہ 'a udhu bil-lah' (I seek protection with Allah) while reciting the Qur’ an which indicates that the Shaitan puts scruples in the heart when one recites the Qur'an. In the verses cited above, there is a refutation of such Satanic instigations.
There are two objectives in reading the Quran—one is for the guidance of the self and the other is to present it to others to encourage them to understand the Truth. Whether the actual words of the Quran are repeated or its meanings are explained, man should in any case seek the protection of God against Satan. It does not mean simply repeating some fixed words; it means consciously arming oneself so that Satan’s attack becomes ineffective. Satan is always lying in wait for man. He changes the meaning of the words of the Quran in the mind of the reader, and what cannot be included in the text he inserts in the commentary. In this way Satan raises controversial issues between the preacher and the addressee, as a result of which understanding the true meaning of the Quran becomes difficult. However, God has given liberty to Satan only to misguide and instigate. He has not given power to him to lead anyone astray by force (laysa lahu sultan). His actions have no effect on those who have maintained their mental connection with God. But those who are neglectful of God and pay attention to the word of Satan become subject to Satan, who leads them towards his evil path.
Uthmani text of the Madinah mushaf (King Fahd Complex). Translation: Saheeh International. Tafsir via Quran.com.