Isn't 'yw' 3rd person? How does it work with 'ti'?
Also, why isn't the order reversed, as with all other sentences of this type I can remember seeing so far?
Garpike's query seems still to need an answer. Why is the verb not rwyt here, and why does Duw not come first? Is the form given here perhaps a somewhat archaic one, different from normal colloquial usage but deemed to be appropriate when addressing the Deity?
"Thou art God" in the King James Bible and older Prayerbook - could we have this as an alternative?