Learning Latin with the Liturgy: the Introit for the Feast of the Elevation of the Holy Cross (September 14)

It was no coincidence that I received a request to grammatically describe this piece. I weekly attend the Elevation of the Holy Cross Eastern Orthodox Church! And as I prepared this post, I found myself singing the song we sing on this Feast Day. I include it below.

The Introit for the Feast of the Elevation of the Holy Cross

Nos autem gloriari oportet in cruce Domini nostri Jesu Christi:

In quo est salus, vita et resurrectio nostra:

Per quem salvati et liberati sumus.

This text echoes Galatians 6:14:

But may it never be that I would boast, except in the cross of our Lord Jesus Christ, through which the world has been crucified to me, and I to the world.

Here is a grammatical description of the Latin of this text.

 Latin Text followed by literal English translation.

Nos autem gloriari oportet in cruce Domini nostri Jesu Christi:

In quo est salus, vita et resurrectio nostra:

Per quem salvati et liberati sumus.

We, however, ought to glory in the cross of our Lord Jesus Christ:
In whom is soundness, life, and our resurrection:
Through whom we have been saved and freed. 

Below is a complete grammatical description of the Introit. But I share first the simply lovely song we Orthodox sing on this Feast Day. We perform the triple prostration you see in the video while we sing the song. 

Latin	English	Parsing	Grammar Points
Nos	We	nom. pl. pronoun	nos, nostri
autem	however		adv.
gloriari	to glory	pres. dep. inf.	glōrior, glōriārī, glōriātus sum
oportet	ought	3rd pers. impers. verb	oportet, oportēre, oportuit
in	in		Prep. + Abl.
cruce	the cross	abl. sing. fem. noun	crux, crucis
Domini	of Lord	gen. sing. masc. noun	Dominus, Domini
nostri	(of) our	gen. sing. masc. poss. adj.	noster, nostra, nostrum; modifies Domini
Iesu	Jesus	gen. sing. masc. name	Iesus, Iesu
Christi	Christ	gen. sing. masc. noun	Christus, Chrisi
in	in		Prep. + Abl.
quo	whom	abl. sing. masc. rel. pronoun	qui, quae, quod; antecedent is Iesu Christi
est	is	3rd pers. sing. pres. ind. verb	sum, esse, fui
salus	soundness	nom. sing. fem. noun	salus, salutatis
vita	life	nom. sing. fem. noun	vita, vitae
et	and		conj.
resurrectio	resurrection	nom. sing. fem. noun	resurrectio, resurrectionis
nostra	our	nom. sing. fem. adj.	noster, nostra, nostrum; modifies resurrectio
Per	Through		Prep. + Acc.
quem	whom	acc. sing. masc. rel. pronoun	qui, quae, quod; antecedent is Iesu Chrisi
salvati	saved	nom. pl. masc. past part.	salvō, salvāre, salvāvī, salvātus
et	and		conj.
liberati	freed	nom. pl. masc. past part.	līberō, līberāre, līberāvī, līberātus
sumus	we (are) have been	1st pers. pl. pres. ind. verb	sum, esse, fui; used paraphrastically to form passive voice of perfect tense with past participles salvati and liberati.