This is the Introit for the feast day (Acts of the Apostles i, 11):
"Ye men of Galilee, why wonder yo, looking up to heaven? alleluia. He shall so come as you have seen Him going up into heaven, alleluia, alleluia, alleluia, Ps. O clap your hands, all ye nations: shout unto God, with the voice of exultation. Glory be to the Father, the Son and the Holy Ghost."
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