A.T. Robertson Commentary John 18:2

"Now Judas also, who betrayed him, knew the place: for Jesus oft-times resorted thither with his disciples." — John 18:2 (ASV)

Resorted thither (συνηχθη εκε). First aorist passive indicative of συναγω, old verb to gather together. A bit awkward here till you add "with his disciples." Judas knew the place, and the habit of Jesus to come here at night for prayer (Luke 22:39). Hence his offer to catch Jesus while the feast was going on, catch him at night and alone in his usual place of prayer (the very spirit of the devil).