14 Propter hoc dabit Dominus ipse vobis signum : ecce virgo concipiet, et pariet filium, et vocabitur nomen ejus Emmanuel.
14 Therefore the Lord himself shall give you a sign. Behold a virgin shall conceive, and bear a son and his name shall be called Emmanuel.
Of all the Advent Hymns this is the one I love the most. I love it for itself and for the happy memories it brings. It's from the 12th-century the text is based on Isaiah 7:14: and the hymn itself is a paraphrasing of the 'O' Antiphons which date back to the 8th century, each of these antiphons deals with a different aspect of Christ's being and the lyrics' call for Christ to come and save us epitomises the sense of expectancy and hope of Advent.
This performance is by the King's Singers. Enjoy :-).