10 “Then the Jews sought Him on the feast-day:” before He went up. For His brethren went up before Him, and He went not up then when they supposed and wished: that this too might be fulfilled which He said, Not to this, that is, the first or second day, to which you wish me to go. But He went up afterwards, as the Gospel tells us, on the middle of the feast.' that is, when as many days of that feast had passed as there remained. For they celebrated that same festival, so far we can understand, on several successive days.
Source: Tractates on the Gospel of John (New Advent)