Matthew
King James Version (KJV)

“Now when Jesus was in Bethany, in the house of Simon the leper,”
King James Version (KJV)
26:6 #Mark 14:3|.
Mt 26:6 Now when Jesus was in Bethany. On the Saturday before. Matthew goes back to an event that occurred at Bethany before the Lord's triumphal entry into Jerusalem, because he is about to relate the treachery of Judas, and it was brought to a crisis by that event. In the house of Simon the leper. Supposed to have been healed by Christ, and a relative of Martha, Mary and Lazarus. Compare the parallel accounts, Mr 14:3 Joh 12:1-2. It is not known certainly who he was.
Because there are so many men in the Bible named Simon...This particular Simon was the the title of "the Leper" to distinguish him from the other Simons, and to remind us that he was healed in Mark 1:40 and is now able to fellowship and have people over at his house...he probabley moved from Galilee (if he was a resident there, or could have only visited to be healed) to Bethany