Mark 10:38

But Jesus said unto them, Ye know not what ye ask. Are ye able to drink the cup that I drink? or to be baptized with the baptism that I am baptized with?

The "cup" and the "baptism" mentioned here are both references to the sufferings and tribulations through which our Lord was passing and which would culminate on the cross itself. "The `cup' is one Jesus is already drinking, and the `baptism' is one which is being experienced .... The `cup' will not be drained until he is taken from the cross."[36] As Dorris said:

This baptism began with his personal ministry and was completed at the cross. He was completely overwhelmed with suffering. Note that he used not the past nor the future tense, but the present.[37]

[36] Ibid., p. 352.

[37] C. E. W. Dorris, op. cit., p. 245.