‘Then comes Jesus with them to a place called Gethsemane, and says to his disciples, “You sit here, while I go over there and pray.” '
We should note as we go through the passage the tenses of the verbs. The present tenses indicate what are almost respites in His turmoil, (He says to them -- He says to them -- He comes to the disciples -- He comes to them'). The past tenses indicate His entering into that turmoil in an emphatic way. ‘He took with Him -- and began to be sorrowful and sore troubled -- He went forward a little, and fell on His face and prayed -- Again a second time He went away and prayed -- He left them and went away and prayed'. He was as it were alone in the oil press, being squeezed dry.
His opening words are preparatory. He must face this alone. ‘You sit here while I go over there and pray'. They will not be further involved until He returns to them at the end. But it is then quite clear that they should have been praying, and were not.