This carol was traditionally sung on `Gaudete Sunday', the third Sunday in Advent. There are several interpretations available on the Internet including those by Steeleye Span by the Oxford Camerata and by Libera with a boys' choir as well as one by dwsChorale in which the words are hear particualrly clearly and which can be heard on the Wikipedia page for the song. The carol was included in the 16th century Finnish/Swedish collection, Piae Cantiones, but may have originated in Bohemia in central Europe. For more details, see the Wikipedia article and also Gaudium mundo, which explains the reference in the third stanza to the gate mentioned in the Old Testament (Ezechiel 44). This was closed after the God of Israel passed through it and would be opened again only for the Prince. The Latin is translated below word-for-word.
Tempus adest gratiae, Time is-here of-grace hoc quod optabamus; this which we-were-wishing-for carmina laetitiae songs of-joy devote reddamus. devoutly let-us-return CHORUS Gaudete! gaudete! Rejoice! rejoice! Christus est natus ex Maria virgine, Christ is born of Mary virgin gaudete! rejoice!
Deus homo factus est, God man made has-been natura mirante; with-nature in-astonishment mundus renovatus est the-world renewed has-been a Christo regnante. by Christ reigning CHORUS
Ezechielis porta Ezechiel's gate clausa pertransitur; that-was-closed is-passed-through unde lux est orta, from-where light has arisen salus invenitur. salvation is-found CHORUS
Ergo nostra contio Therefore our gathering psallat iam in lustro, let-it-sing now in offering benedicat Domino: let-it-bless the Lord: salus Regi nostro. greeting to our King CHORUS