Is it possible for a Christian to be possessed?

Yes, Christians can be affected by demons, but cannot be owned(possessed) by demons. They can affect your mind and your body.

I suggest contact direct, I am in WA.

God bless.

Consider both Peter, Paul and Judas for an example in the word of the interactions between Jesus, people, Satan.

Satan entered into Judas, so Judas became possessed.
Judas though was the traitor, and also appointed to this to fulfill scripture.

Peter and Paul the LORD allowed some interaction with Satan into their life, but they were saved. For Peter, some needed disciplining, for Paul to keep Paul humble. This was under the control and authority of Jesus the entire time.

Luke 22

Now the Feast of Unleavened Bread drew near, which is called Passover. 2 And the chief priests and the scribes sought how they might kill Him, for they feared the people.

3 Then Satan entered Judas, surnamed Iscariot, who was numbered among the twelve. 4 So he went his way and conferred with the chief priests and captains, how he might betray Him to them. 5 And they were glad, and agreed to give him money. 6 So he promised and sought opportunity to betray Him to them in the absence of the multitude.

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Peter was only oppressed, being used by Satan, Jesus rebuked Satan who was speaking through Peter.

21 From that time Jesus began to show to His disciples that He must go to Jerusalem, and suffer many things from the elders and chief priests and scribes, and be killed, and be raised the third day.

22 Then Peter took Him aside and began to rebuke Him, saying, “Far be it from You, Lord; this shall not happen to You!”

23 But He turned and said to Peter, “Get behind Me, Satan! You are an offense to Me, for you are not mindful of the things of God, but the things of men.”

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Jesus also says to Peter, when you have turned strengthen your brothers.
Luke 22

31 And the Lord said,[c] “Simon, Simon! Indeed, Satan has asked for you, that he may sift you as wheat. 32 But I have prayed for you, that your faith should not fail; and when you have returned to Me, strengthen your brethren.”

33 But he said to Him, “Lord, I am ready to go with You, both to prison and to death.”

34 Then He said, “I tell you, Peter, the rooster shall not crow this day before you will deny three times that you know Me.”

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2 Corinthians 12:7

The Thorn in the Flesh

7 And lest I should be exalted above measure by the abundance of the revelations, a thorn in the flesh was given to me, a messenger of Satan to buffet me, lest I be exalted above measure.

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