Is the statement "Listen to the voice of our Lord within you" doctrinally and religiously sound?

Perhaps what is meant by "the voice of Allah" is Allah's admonisher in the heart of the believer, as came in the hadith of Ibn Mas'ud, in which the Prophet, peace and blessings be upon him, gave an example of the Straight Path and Allah's prohibitions, and he explained "the caller from above it" as being Allah's admonisher in the heart of every believer, which is the touch of the angel or his proofs and insights.

This attribution to Allah is of the type of attributing entities (created things), not divine attributes. For whatever is attributed to Allah Almighty and is an entity subsisting by itself, it is not an attribute of Allah.

So there is no harm in that if the speaker intends Allah's admonisher or the like. However, if he intends Allah's voice, which is an attribute among His attributes, then he has spoken about Allah without knowledge.