A.T. Robertson Commentary Luke 24:33

"And they rose up that very hour, and returned to Jerusalem, and found the eleven gathered together, and them that were with them," — Luke 24:33 (ASV)

That very hour (αυτη τη ωρα). Locative case and common Lukan idiom, at the hour itself. They could not wait.

Gathered (ηθροισμενους). Perfect passive participle of αθροιζω, old verb from αθροος (copulative α and θροος, crowd). Only here in the N.T.