Matthew 26:38

Then saith he unto them
The three disciples, Peter, James, and John, who, by his looks and gestures, might know somewhat of the inward distress of his mind; yet he choose to express it to them in words, saying,

my soul is exceeding sorrowful, even unto death.
That Christ had an human soul, as well as an human body, is clear from hence; and which was possessed of the same passions as ours are, but without sin, such as joy, love, grief, sorrow and at this time its sorrows were exceeding great: his soul was beset all around with the sins of his people; these took hold on him, and encompassed him, which must, in the most sensible manner, affect his pure and spotless mind; the sorrows of death and hell surrounded him on every side, insomuch that the least degree of comfort was not let in to him; nor was there any way open for it, so that his soul was overwhelmed with sorrow; his heart was ready to break; he was brought even, as it were, to the dust of death; nor would his sorrows leave him, he was persuaded, until soul and body were separated from each other; see a like phrase in ( Judges 16:16 ) ,

tarry ye here.
The Ethiopic adds, "till I shall return", for he was going a little further from them, to vent his grief, and pour out his soul unto God. Munster's Hebrew Gospel reads it, "expect me", or "wait for me here", signifying, that he should return to them shortly;

and watch with me.
It was night, and they might be heavy and inclined to sleep: he knew it would be an hour of temptation both to him and them, and therefore advises them to watch against it; and to observe how it would go with him, and what should befall him, that they might be witnesses of it, and be able to testify what agonies he endured, what grace he exercised, and how submissive he was to his Father's will.