Mark 13:4
"Tell us when these things shall be, and what shall be the sign that all these predictions are about to be fulfilled."
Acts 1:6-7
So, when they came together, they began to ask him, "Master, are you at this time about to restore the kingdom of Israel?"
Matthew 24:3
When he had seated himself on the Mount of Olives, his disciples came to him privately, saying, "Tell us, when will these things happen, and what will be the sign of your coming, and of the end of the age?"
Luke 21:7
"Teacher, when will this be?" they asked him, "and what shall be the sign that these things are about to happen?"
John 21:21-22
On catching sight of him, Peter said to Jesus, "Lord, what about him?"