Luke 24:44-48(KJV)
44 And he said unto them, These are the words which I spake unto you, while I was yet with you, that all things must be fulfilled, which were written in the law of Moses, and in the prophets, and in the psalms, concerning me. 45 Then opened he their understanding, that they might understand the scriptures, 46 And said unto them, Thus it is written, and thus it behooved Christ to suffer, and to rise from the dead the third day: 47 And that repentance and remission of sins should be preached in his name among all nations, beginning at Jerusalem. 48 And ye are witnesses of these things.

Christ appeared to the disciples again after his resurrection to strengthen their faith. They first feared His appearance but they gained confidence it was Christ as He spoke with them and dined with them. Christ then opened their minds to understand the meaning of the scriptures and that what must have happened did happen. Christ rose from the dead and now repentance and remission of sins was to be preached to all nations. These disciples were the witnesses to His words.

Chuck Swindoll, in Embraced by the Spirit (Zondervan 2010) wrote:

One of my most unforgettable moments happened when I was about ten years old. My father served our country during World War II in a plant in our hometown, building all sorts of interesting equipment for the massive tanks, fighter planes, and bombers that defended us in lands far away. Dad worked too long and too hard. As a result he suffered a physical breakdown. And on its heels came an emotional trauma that puzzled everyone, including the doctors.

I was convinced in my heart that my dad was going to die. He may have had such thoughts too, because one night he called me into his room for a somber father-son talk �. I remember leaning hard against his bed, listening carefully to a voice that was hardly more than a whisper. I thought I was hearing him for the last time. He gave me counsel on life�how I should live, how I should conduct myself as his son. The counsel wasn't long, and then I left and went across the hall to the room that I shared with my older brother. All alone, I lay across my bed and sobbed, convinced that I would never see my dad alive again.

That scene still haunts me. Even though my dad recovered to live � I still remember the night he talked to me. Something very significant is wrapped up in our final words. Consider the night in Jerusalem when the Lord and his disciples gathered for � what we call "The Last Supper." Less than twelve hours after [that meal], Jesus was nailed to a cross; a few hours later, he was dead. Jesus understood the significance of those moments and the importance of his last counsel. And so he gave them exactly what they would need to carry them through the rest of their days.