CC Madhya 6.180

ācāryera doṣa nāhi, īśvara-ājñā haila
ataeva kalpanā kari’ nāstika-śāstra kaila

ācāryera—of Śaṅkarācārya; doṣa—fault; nāhi—there is not; īśvara-ājñā—the order of the Supreme Personality of Godhead; haila—there was; ataeva—therefore; kalpanā—imagination; kari’—making; nāstika—atheistic; śāstra—scriptures; kaila—prepared.

“Actually there is no fault on the part of Śaṅkarācārya. He simply carried out the order of the Supreme Personality of Godhead. He had to imagine some kind of interpretation, and therefore he presented a kind of Vedic literature that is full of atheism.