6 Bible Verses about Testing Spirits

Beloved, every spirit believe not, but prove the spirits, if of God they are, because many false prophets have gone forth to the world;

and to another in-workings of mighty deeds; and to another prophecy; and to another discernings of spirits; and to another divers kinds of tongues; and to another interpretation of tongues:

in this know ye the Spirit of God; every spirit that doth confess Jesus Christ in the flesh having come, of God it is, and every spirit that doth not confess Jesus Christ in the flesh having come, of God it is not; and this is that of the antichrist, which ye heard that it doth come, and now in the world it is already. Ye -- of God ye are, little children, and ye have overcome them; because greater is He who is in you, than he who is in the world.read more.
They -- of the world they are; because of this from the world they speak, and the world doth hear them; we -- of God we are; he who is knowing God doth hear us; he who is not of God, doth not hear us; from this we know the spirit of the truth, and the spirit of the error.

and these were more noble than those in Thessalonica, they received the word with all readiness of mind, every day examining the Writings whether those things were so;

all things prove; that which is good hold fast;

and because from a babe the Holy Writings thou hast known, which are able to make thee wise -- to salvation, through faith that is in Christ Jesus; every Writing is God-breathed, and profitable for teaching, for conviction, for setting aright, for instruction that is in righteousness, that the man of God may be fitted -- for every good work having been completed.