This depends strictly on who you are refering to afterall God is a spiritual being so communication with God of heven is not evil and nor is rebuking Satan. What is absolutely out of bounds is communication with familiar spirts (demons).
These beings know our weaknesses, they know what to tell us and when to tell us. So if you are vulnerable and some smooth talking, fresh faced assecended master comes a knocking and tells you that you are great, then hey! See what I mean. The confidence trickster playing the long game. These things are frighteningly evil and I give praise to God almighty and Lord Jesus Christ for salvation and protection from these abominations.
I mean, your eating breakfast and just about to drink your tea in peace when Satan whispers in your ear “you are a sinner, you are not worthy to be a Christian”. So, understand that:
1) Satan can communicate with you.
You recognise what just happened and rebuke him “Lord rebuke you”.
2) You can communicate with Satan.
You then pray to God, repent your sins and ask for guidence.
3) You can talk to God.
God responds in many different ways. Sometimes through actions, or direct thoughts or vocally or some other way. Satan and his minions can also do this but they are the counterfiet, God of heaven is truth.
Rationale: The difference between a medium and a non-medium or a channeller and a non-channeller is an ability to recognise spiritual communication from personal/natural thoughts. The difference between a christian filled with the holy spirit and a non-christian is the ability of spiritual discernment. Since without such a connection to God it is impossible to know otherwise.