As has been stated, in both the case of the psychic and the prophet, there is communication between man and a spirit. In the case of a psychic, that spirit is probably of the Devil, in the case of the prophet, that Spirit is the Spirit of God. That is why amongst the skills of a mature Christian and the gifts of the Spirit is that of "distinguishing amongst the spirits"
As 1 Corinthians 12:8 - 10 states:
To one there is given through the Spirit a message of wisdom, to another a message of knowledge by means of the same Spirit, to another faith by the same Spirit, to another gifts of healing by that one Spirit, to another miraculous powers, to another prophecy, to another distinguishing between spirits, to another speaking in different kinds of tongues, and to still another the interpretation of tongues.
An interesting case presents itself in Acts 16, in which Paul is being tailed by a young girl with psychic powers. She is called a "diviner" or a "fortune teller" in the ESV. As Acts states it:
16 Once when we were going to the place of prayer, we were met by a female slave who had a spirit by which she predicted the future. She earned a great deal of money for her owners by fortune-telling. 17 She followed Paul and the rest of us, shouting, “These men are servants of the Most High God, who are telling you the way to be saved.” 18 She kept this up for many days. Finally Paul became so annoyed that he turned around and said to the spirit, “In the name of Jesus Christ I command you to come out of her!” At that moment the spirit left her.
Here we had a psychic who was telling the truth, but clearly in a fashion that was not from God. It fits all the points of the assertion - a spirit and - unknown origin. Paul, gifted by God, casts out the evil spirit.
The story goes on to say that this girl's owner became irate, because "their hope of making money from her was gone." This leads me to a simple test that, while not 100%, would cover what I think of as the garden variety psychic who has a fortune telling storefront. The test is this - is the gift being used to make money? If so, it is clearly not from God.
This is supportable through a few other instances of Scripture:
- 2 Kings 5 tells the story of Elisha healing Naaman of leprosy. After he does this, it says:
16 The prophet answered, “As surely as the LORD lives, whom I serve, I will not accept a thing.” And even though Naaman urged him, he refused.
Elisha's servant, however, desires this tribute, and when he accepts it, the servant becomes a leper himself. God is a jealous God, he shares his Glory with no other, and clearly needs no reward for what he does.
- Acts 8 tells the story of Simon the Magician, after whom we get the term simony
In this story, Simon is a believer, but desires power from God in order to make money from it. Peter says:
20 Peter answered: “May your money perish with you, because you thought you could buy the gift of God with money! 21 You have no part or share in this ministry, because your heart is not right before God. 22 Repent of this wickedness and pray to the Lord in the hope that he may forgive you for having such a thought in your heart. 23 For I see that you are full of bitterness and captive to sin.”
In short, then, the answer is, No. A Good Christian would not use his psychic gifts as is normally done. The source of the spirit must be known, and if the gift is being used gain, it is clearly not from God.