He is risen, indeed!
My dad used to always say to us on Easter morning, "He is risen!" And we would respond, "He is risen, indeed!" The tradition has its origins in the First Century church, when Christians would greet each other with these words.
It continued into Eastern Orthodox religions and our pastor tells about being in an Eastern European country on Easter Sunday and the pastor of the church where he was visiting welcomed the congregation with "He is risen" and they responded with "He is risen, indeed!" The pastor said it again, and the congregation responded. A third time it was spoken and the response was given. I tried to verify this for certain, but I believe that the reason for the three sayings of "He is risen. He is risen, indeed" is to signify the three days that Jesus was in the tomb.
But He's not there! He is risen! He is risen, indeed! Happy Resurrection Day!