Task: Text Simplification
Input (English): the apostolic tradition , attributed to the theologian hippolytus , attests the singing of hallel psalms with alleluia as the refrain in early christian agape feasts.
Output (English): the apostolic tradition , connected to the scientist hippolytus who is an expert in theology , starts the singing of hallel psalms with alleluia as the repeated line in early christian lovable and wonderful festivals.