because it is needed to make the person addressed understand in his own language, while the sound meaning is made clear, there is [no harm in that, for it is permissible] (1) to translate the Quran and hadith when needed to convey their meaning. Many people have become accustomed to a particular mode of expression; if they are not addressed in it, they neither understand nor can they discern (2) whether a statement is sound or false. They may even accuse the person addressing them of not understanding what he is saying.
Most of those who delve into speculative theology and philosophy are of this kind: you may present one of them (3) with sound meanings through scriptural texts, yet they will not accept them, supposing that their own terminology contains meanings absent from those texts. But when the meaning indicated by revealed law is taken and formulated (4) in their terminology, and is used (5) to demonstrate the falsity of their position, which contradicts the meaning established by revelation, they submit to it (6) and acquiesce.
This is like addressing a Turk, a Berber, [a Byzantine] (7), or a Persian with the Quran in Arabic and explaining it to him: he will not understand until something is translated for him into his own language (8). His happiness and joy then become immense, and he accepts the truth and abandons his falsehood, because the meanings brought by the Messenger are the most perfect, finest, and soundest of meanings. This, however, requires complete mastery of both, like an interpreter who [wishes to] be skilled in understanding both languages (9).