Eph. 1:17-18
In order to detect which is the "voice of God," and which is the "voice of the devil," we need to understand that the Holy Spirit alone is charged to communicate the will of God to the believer, and that He works from within the spirit of the man enlightening the understanding ( Eph. 1:17-18; top ), so as to bring him into intelligent co-working with the mind of God.
The purpose of the Holy Spirit is, briefly, the entire renewal of the redeemed one, in spirit, soul and body, He therefore directs all His working to the liberation of every faculty, and never in any way seeks to direct a man as a passive machine, even into good. He works in him to enable him to choose the good, and strengthens him to act, but never - even for "good" - dulls him, or renders him incapable of free action, otherwise He would nullify the very purpose of Christ's redemption on Calvary, and the purpose of His own coming.
When believers understand these principles, the "voice of the devil" is recognizable, i.e.,
1) when it comes from outside the man, or within the sphere of his circumference, and not from the central depth of his spirit, where the Holy Spirit abides;
2) when it is imperative and persistent, urging sudden action without time to reason, or intelligently weigh the issues;
3) when it is confusing and clamorous, so that the man is hindered from thinking;
for the Holy Spirit desires the believer to be intelligent, as a responsible being with a choice, and will not confuse him so as to make him incapable of coming to a decision.
The speaking of evil spirits can also be a counterfeit of the apparent inner speaking of the man himself, as if he were himself "thinking," and yet with no concentrated action of the mind; e.g., a persistent and ceaseless "commentary" going on somewhere within, apart from volition or mind action, commenting on the man's own actions or the actions of others, such as "you are wrong," "you are never right...God has cast you off...you must not do that," etc., etc.
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