He was not a good priest. He ended up throwing me out of the church. Not because of the Latin, though. That is a long story, for another time. When presiding at Mass this particular priest always garbles his way through the words as quickly as he can; I'm not sure why he does this, but he always does. He decided to conduct a Latin mass but didn't know I understood Latin; not fluently, but well enough for a text that is familiar anyway. When he found out he was unhappy but it was too late to back out. So I went and he did his best (in fact he did perfectly well; Latin is pretty well phonetic), and I said the responses, as you do. But he wasn't happy at all. He thought he did badly (he didn't) and that I was laughing at him (I wasn't, but he was very insecure). In all the time I was there he didn't hold another Latin mass.
The beautiful Tallis you posted sounds very much like the singing in tongues sometimes heard in some congregations, expressing ecstacy in worship as directed by the Holy Spirit in words beyond human understanding. It's not the words that matter, it's the 'feelings' which express the worship. .
But you just like the tune. The words are hardly edifying. They depict a cry of despair against cruel fate. O Fortune, like the moon you are changeable, ever waxing, ever waning, hateful life first oppresses and then soothes as fancy takes it; poverty and power it melts them like ice fate – monstrous and empty, you whirling wheel, you are malevolent, well-being is vain and always fades to nothing, shadowed and veiled you plague me too; now through the game I bring my bare back to your villainy fate is against me in health and virtue, driven on and weighted down, always enslaved. so at this hour without delay pluck the vibrating strings; since Fate strikes down the strong man, everyone weep with me! Effectively a celebration of the triumph of darkness over light. The fact that you seem not to have understood the words but just like the tune, means you have probably been missing a lot, but just enjoy remaining ignorant. I agree it's a good tune though. .
I personally find the lyrics to be both beautiful and powerful if viewed in the right context. The original text was almost certainly based on The Consolation of Philosophy by Boethius. In Boethius' work, Lady Philosophy (God in another guise to better relate with the Greek and Roman intellectual schools of the time) is comforting Boethius before his execution and eventually leads to the author's conversion. Lady Philosophy uses a similar poem to the text of O Fortuna, in some places word for word, to show Boethius the hopelessness of the Greek and Roman pagan belief systems especially Fortuna, and introduce him to the idea of free will and a loving God. The author of O Fortuna most likely a Goliard, probably didn't have such a noble intention behind his poem but a positive message can still be taken away. I view the piece as a ballad against determinism, nihilism, and the all too common obsession with the transient instead of transitory nature of human existence. Dr. Corey Olsen has a fascinating lecture series on The Consolation of Philosophy that covers the connection between the two works.
Very valid points made here. The music and the words are intended to convey to the hearer the sense of despair felt by those who have no faith and feel themselves at the mercy of attack by fickle FATE and futility. As such, it is a powerful meditation. As a recommended philospohical attitude to life it is considerably less edifying than the sermon on the mount though. Admittedly however, that is clearly not its purpose, so it can be forgiven if mistaken for that. .
I quite enjoy liturgy and chants in Latin, but it's important to provide translations for those who have no fluency in it.
If the choir sing something in Latin, that’s fine. I have attended the Traditional Latin Mass in Catholic Churches on a few occasions. The congregation mostly just sits there and stares at the priest.