“Beginning from the baptism of John, unto that same day that he was taken up from us, must one be ordained to be a witness with us of his resurrection.” Acts 1:22
One of the requirements for the man picked to replace Judas was that he had to be a witness of the resurrection of Jesus Christ. It is still the same today. Though we may have not seen His physical body, we cannot be effective witnesses for the Lord unless we have seen His resurrection through our own experience with resurrection power. Without the power encounter of the new birth, there is no resurrection life. If there is no resurrection life then there is no resurrection to be seen.