大乘起信論義記 2.144

2.144

言智淨相者，明本覺隨染還淨之相。不思議業相者，明還淨本覺業用之相。此之二相若離染緣則不得成，故云隨染也。

'The mark of the purity of wisdom' explains the mark of innate enlightenment returning to purity in accordance with defilement. 'The mark of inconceivable karma' explains the mark of the karmic functioning of innate enlightenment returning to purity. If these two marks were separated from defiled conditions, they could not be established; hence it says 'in accordance with defilement.'