I'm going to introduce you to the legendary Fr. Stephanous Rizk, legendary because he stands out as the only priest who was recorded to have prayed the now extinct Coptic liturgy of St. John the Apostle, which can be referenced here from the Ethiopian liturgy pdf on page 64:
https://drive.google.com/file/d/0B0sMVN64GCA3d0oxUVJlaDg2Zmc/edit?usp=sharing
The reason why it's not prayed anymore is due to synodal restrictions, wishing to standardize all liturgies to be done in any of the three allowed, the Basilian, the Gregorian, and the Cyrillian liturgies (probably restricted because of its peculiar way in oscillating back and forth between praying to the Father and praying to the Son, which may cause confusion). Nevertheless, the Johannine is still chanted in the Ethiopian/Eritrean Orthodox churches. It's depth of theological language is evident, along with its Trinitarian, Christological, and Soteriological implications with language of deification (as water is mixed with wine, the priest asks the Son to unite His divinity with our humanity, His greatness with our humility):
http://www.youtube.com/watch?v=qpf3cxe6g-4
The same priest also has a recording of one of my favorite fractions, the Fraction to the Son from the Cyrillian Liturgy, which is also rich with very evocative language of theosis:
https://soundcloud.com/fady-nassif/a9pmbpb5fqiv
I think it's worthwhile actually quoting the whole fraction for you, as a very important part of Coptic tradition and theology:
O Lamb of God who carried the sins of the world through Thy suffering; with Thy tenderness, erase our sins.
O Only-Begotten Son of God, Who with Thy pain purified the world; with Thy mercy, purify our souls.
O Christ, Who through Thy death conquered death; Raise our souls from death.
O Thou Who accepted the oblations, Who for the sinners, offered Thyself. Accept repentance from us sinners.
For we came forth to Thee without justifications, knocking on the door of Thy kindness. Grant us, O Treasure of mercies, healing with Thy precious remedies.
Heal, Merciful One, our miserable souls by the ointments of Thy life-giving sacraments.
Purify our bodies, cleanse us from our iniquities, make us worthy for the descent of Thine pure Spirit upon our souls.
Enlighten our minds so we can see Thy praise, purify our thoughts and blend us with Thy glory.
Thy love lowered Thyself down to our level and Thy grace raises us to Thine height.
Thy kindness obliged Thee to incarnate in our flesh. Thou revealed Thy mystery to us.
Reveal in the souls of Thy servants the glory of Thine hidden sacraments.
And when this sacrament is raised on Thine altar, sin will vanish from our bodies by Thy grace.
When Thy glory descends on Thy sacrament, our minds are lifted up to see Thy majesty.
On the change of the bread and wine to the Body and Blood, our souls will change to share in Thy glory, and unite with Thy Divinity.
Create in us, O Lord our God, a pure heart, let Thy Spirit dwell inside us.
Renew our senses with Thy power and make us worthy of Thy gift.
From the Cup of Thy Blood, we drink, give us the spiritual taste to enjoy Thy life-giving sacraments.
We come forward to Thee sure of Thy mercy and Thou dwell in us through Thy love.
Fill us with Thy feat and inflame our hearts with the eagerness of Thee.
Pour into us Thy grace and purify our sense by Thy mercy.
Give us sincere tears and cleanse us from the defilement of sin.
Make us sanctified temples for Thy presence and purified vessels to accept Thee.
So that by tasting Thy Flesh, we become worthy of tasting Thy grace; and by drinking Thy Blood, we become worthy of the sweetness of Thy love.
Thou granted us to eat of Thy Flesh openly, make us worthy to unite with Thee secretly.
Thou granted us to drink Thy Blood openly, grant us to blend with Thy purity secretly.
And as Thou art One with Thy Father and Thine Holy Spirit, we become united with Thee, and Thou with us to fulfill Thy saying, “And that we all may be one in us.”
So with that intimacy, we call on God, Thy Father, our Father, and say with loud voices:
Our Father …
from http://e.copticbook.net/index.php?b=20101101001&f=0518&h=0
