Tradition
St. John Chrysostom
Homilies on the Gospel of John
Homily 83 › John 18:11
“The cup which My Father has given Me, shall I not drink it?”
Showing, that what was done proceeded not from their power, but from His consent, and declaring that He was not one opposed to God but obedient to the Father even unto death.
Source: Homilies on the Gospel of John (New Advent)