http://apologeticspress.org/AllegedDiscrepancies.aspx?article=2025&b=John
When Did Satan Enter Judas?
by Eric Lyons, M.Min.Q.
On the evening before His crucifixion, Jesus met with His disciples in Jerusalem to eat the Passover meal. According to John’s gospel account, “Satan entered” Judas during the meal (13:27). Luke, however, recorded that “Satan entered Judas” prior to the Passover meal (22:1-7). Is this a contradiction?A.
If the Bible writers had indicated that Satan only entered Judas once during his lifetime, and that occasion was mentioned in the Bible as being at two different times, then skeptics would have a reasonable argument. The truth is, however, Satan easily could have entered Judas more than once, just as evil spirits and demons entered people in the past multiple times. [NOTE: We are not informed exactly what is meant by Satan “entering” Judas. It could simply mean that Satan had a strong influence on Judas and filled his heart with evil passions, similar to how he “filled” Ananias’ heart to lie to the Holy Spirit—Acts 5:3.]The Old Testament reveals that King Saul was overcome with an “evil spirit” at various times throughout his reign. After Samuel anointed David to be the future king of Israel, “the Spirit of the Lord departed from Saul, and an evil spirit from the Lord terrorized him” (1 Samuel 16:14, NASB). Then, following David’s battle with Goliath, “an evil spirit from God came mightily upon Saul, and he raved in the midst of the house” (1 Samuel 18:10, NASB; cf. 19:9). Also, “[w]henever the evil spirit from God came to Saul, David would take the harp and play it with his hand; and Saul would be refreshed and be well, and the evil spirit would depart from him” (1 Samuel 16:23, NASB, emp. added).
If an evil spirit could “come upon Saul” and “depart from him” at various times throughout his reign, and if, as Jesus indicated in the first century, unclean spirits or demons could go in and out of someone (Luke 11:24-26), then it is logical to conclude that Satan could have “entered” and “departed” from Judas on more than one occasion. In fact, that is exactly what happened. Prior to John’s mention of Satan entering Judas, he noted how the devil had “already put it into the heart of Judas Iscariot, Simon’s son, to betray Him [Jesus]” (John 13:2, emp. added). Luke explained how, prior to the Passover meal, Judas met with Jesus’ enemies and made an agreement with them to betray Jesus at some secluded location (22:1-7). Later, during the Passover meal, “Satan entered Judas” again (John 13:27).
There is no contradiction here, just accounts of two different occasions when Satan entered Judas.