Does this verse imply that some of the Quran is confusing?

This verse establishes a fundamental principle for interpreting the Quran: some verses are precise and clear, while others are ambiguous or can be misinterpreted if taken out of context. The second category must be understood in light of the first, with the clear verses guiding the interpretation of the ambiguous ones.

An example of this is found in a report about the occasion for the revelation of this verse. When a delegation of Christians from Najran met the Prophet Muhammad ﷺ, they attempted to support their belief in the Trinity by citing Quranic verses that describe Jesus (peace be upon him) as a "word from God" and a "spirit from Him" (e.g. 4:171). However, they ignored the many explicit verses (e.g. 112:1-4) that affirm the doctrine of Monotheism and clearly state that Jesus is an honored servant and messenger of God (e.g. 19:30).

Regarding the decisive verses (ayat muhkamat), Allah says, “They are the essence of the Book.” In his commentary, Ibn ‘Atiyyah explains that these decisive verses form the majority of the Qur'an and serve as the foundation of its teachings, as they are numerous, detailed, and leave nothing unexplained. In contrast, the ambiguous verses, which are open to interpretation and require careful contemplation, are fewer in number.

Ibn ‘Atiyyah further clarifies that this verse initially refers to the Christians of Najran and the Jews who were contemporaries of the Prophet Muhammad ﷺ, as they would challenge the meanings of the Quran. However, it also applies more generally to all those who deviate by misinterpreting the Quran—whether they are disbelievers, heretics, or ignorant innovators. The term "deviation" here refers to straying from the truth and proper guidance. Those who deviate ignore the decisive verses which would provide them guidance, and instead focus on the ambiguous ones, seeking to cause discord and mislead others.

Ambiguous verses of the Quran have to be read in context of the rest of the Quran, particularly those verses that are clear and explicit. Not doing so is a sign of ill intent.