“Jesus said to them.
‘I am deeply grieved,
Even to death.
καὶ λέγει αὐτοῖς Περίλυπός ἐστιν ἡ ψυχή μου ἕως θανάτου· μείνατε ὧδε καὶ γρηγορεῖτε
This is almost exactly word for word in Matthew, chapter 26:38. Mark indicated that Jesus said to his 3 favorite apostles (καὶ λέγει αὐτοῖς) that he was very sorrowful or deeply grieved (Περίλυπός ἐστιν ἡ ψυχή μου), even unto death (ἕως θανάτου). He wanted them to stay there (μείνατε ὧδε) to watch, and remain awake or vigilant (καὶ γρηγορεῖτε). Thus, began the so-called agony of Jesus in the garden.
“Jesus took with him
To be distressed
καὶ παραλαμβάνει τὸν Πέτρον καὶ τὸν Ἰάκωβον καὶ τὸν Ἰωάνην μετ’ αὐτοῦ, καὶ ἤρξατο ἐκθαμβεῖσθαι καὶ ἀδημονεῖν,
This is almost word for word in Matthew, chapter 26:37, where James and John were simply called the sons of Zebedee. In Luke, chapter 22, and in John, chapter 18, there was no mention of these 3 favorite apostles being separated from the others. Mark indicated that Jesus took with him Peter, James, and John (καὶ παραλαμβάνει τὸν Πέτρον καὶ τὸν Ἰάκωβον καὶ τὸν Ἰωάνην μετ’ αὐτοῦ). These were the same 3 apostles who were with Jesus at the transfiguration. Jesus then began to be grieved, pained, sorrowful, troubled, awestruck, distressed, and agitated (καὶ ἤρξατο ἐκθαμβεῖσθαι καὶ ἀδημονεῖν). This story showed the vulnerability of Jesus in his suffering.