Intellectual perception

[boccaderlupo]

"...It is exactly the same with us in relation to the attacks of the evil spirits. Even if you repel the heavenly spirits, they will be gladdened by this, and will help you to participate still further in grace: because of this proof of your love for the Lord they will fill you brim-tull with spiritual delight. So do not from light-mindedness speedily surrender yourself to the visitations of spirits, even if they are heavenly angels, but be wary, submitting them to the most careful scrutiny. Thus you will welcome the good and repel the evil...

According to St. Paul, Satan can even change himself into an angel of light in order to practise his deceptions (cf. 2 Cor. 11.: 14); yet though he may manifest himself in such a glorious manner, he cannot, as we said, produce within us the effects of grace, and so it becomes quite clear that the vision is counterfeit. For the devil cannot bring about love either for God or for one's neighbour, or gentleness, or humility, or joy, or peace, or equilibrium in one's thoughts, or hatred of the world, or spiritual repose, or desire for celestial things; nor can he quell passions and sensual pleasure. These things are clearly the workings of grace. For the fruits of the Spirit are love, joy, peace, and so on (cf. Gal. 5 : 22), while the devil is most apt and powerful in promoting vanity and haughtiness.

You may know from its effect whether the intellectual light shining in your soul is from God or from Satan. Indeed, once it has developed its powers of discrimination, the distinction is immediately clear to the soul itself through intellectual perception." — St. Macarius of Egypt, as paraphrased by St. Symeon Metaphrastis, Patient Endurance and Discrimination

Emphases mine. "Hatred of the world" is a little strong (in this case, giving the saint the benefit of the doubt that he means "worldly" things, i.e. unreasonable attachments to material things, of 'the flesh"), but the gist of the above is clear. There's a distinction to be made between spirits, and the infernal spirits cannot produce things like joy and peace, but instead incline one to the passions and/or arrogance and the like.

Again, a merry belated Christmas to all those who celebrate, and may you walk forever in the Light.