This marks a transition from the narrative of the "People of the Cave" to a direct command regarding the recitation and preservation of divine revelation. It establishes a fundamental theological principle regarding the immutability of God’s decrees.
Surah 18:27:
"And recite that which hath been revealed unto thee of the Scripture of thy Lord. There is no changing His words, and thou wilt find no refuge beside Him."
The phrase "La mubaddila li-kalimatihi" is one of the most significant declarations in the Quran regarding textual integrity. It appears in several places (cf. 6:34, 6:115, 10:64) and forms the basis for the following theological arguments:
The verse asserts that no human or external force has the power to alter, replace, or distort the words of God. This is often interpreted in two ways:
It refers specifically to the protection of the Quran but refers to "His Words" (Kalimatihi) as a general category.
Since the Torah, the Psalms, and the Gospel are also defined as "the words of Allah" in the Islamic tradition, this verse implies that those previous revelations were also under divine protection from corruption.
The verse begins with the command to "recite" (utlu). In the 7th-century context, this was an instruction to Muhammad to convey what was currently being revealed to him.
By pairing the command to recite with the statement that the words cannot be changed, the verse links the current recitation to an unchangeable source.
The conclusion of the verse—"and thou wilt find no refuge beside Him"—emphasizes the exclusivity of God's authority.
If one seeks to change the words or follow a corrupted path, there is no spiritual safety or alternative protector.
If God's words cannot be changed, then the scriptures revealed to Moses (Torah), David (Zabur), and Jesus (Injil) must have remained intact, at least until the time of the Quran's revelation.
This creates a point of study regarding how the Quran can "confirm" previous books while also containing theological differences from the manuscripts of those books held by the 1st-century and 7th-century communities.
The phrase "No changer of His words" is often contrasted with the concept of naskh (abrogation), where one verse of the Quran is replaced by another. It is difficult to reconcile the idea that God's words are "unchangeable" with the internal practice of abrogation!