John Gill Commentary Mark 14:34

"And he saith unto them, My soul is exceeding sorrowful even unto death: abide ye here, and watch." — Mark 14:34 (ASV)

And says to them
The above three disciples;

my soul is exceeding sorrowful unto death :
he was surrounded with sorrow, and it pressed him so hard, and close, on every side, that he was just ready to die with it:

stay you here, and watch :
in Matthew it is added, "with me": (See Gill on Matthew 26:38).