A.T. Robertson Commentary Luke 22:10

"And he said unto them, Behold, when ye are entered into the city, there shall meet you a man bearing a pitcher of water; follow him into the house whereinto he goeth." — Luke 22:10 (ASV)

When you are entered (εισελθοντων υμων). Genitive absolute.

Meet you (συναντησε υμιν). An old verb συνανταω (from συν, with, and ανταω, to face, αντ) with associative instrumental (υμιν). See on Mr 14:13 about the "man bearing a pitcher of water."