Cyril of Alexandria
Catena Aurea · Lukasevangelium 17
And he said unto the disciples, The days will come, when ye shall desire to see one of the days of the Son of man, and ye shall not see it. And they shall say to you, See here; or, see there: go not after them, nor follow them. For as the lightning, that lighteneth out of the one part under heaven, shineth unto the other part under heaven; so shall also the Son of man be in his day. But first must he suffer many things, and be rejected of this generation.
Now His disciples supposed that He would go to Jerusalem, and would at once make a manifestation of the kingdom of God. To rid them therefore of this belief, He informs them that it became Him first to suffer the Life-giving Passion, then to ascend to the Father and shine forth from above,that He might judge the world in righteousness. Hence He adds, But first must he suffer many things, and be rejected of this generation.