Listen to Agnus Dei / O Come Let Us Adore Him (Medley) online. Agnus Dei / O Come Let Us Adore Him (Medley) is an English language song and is sung by Don Moen. Agnus Dei / O Come Let Us Adore Him (Medley), from the album Christmas: A Season of Hope, was released in the year 2014. The duration of the song is 5:32. Download English songs online from JioSaavn.