Deus (Ego) Sum.
Ego = I and is contained in the verb so it can be omitted and usually is.
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OK, now that someone has gone and changed the question to "With God I Am" That changes everything: In English, when you say someone is "With God" that can mean that they are living a sanctified life or that the person is dead.
- I am dead: Sum mortuus.
- I am in Paradise: Sum in Paradiso. (Compare to Luke 23:43--et dixit illi Iesus amen dico tibi hodie mecum eris in paradiso. And Jesus said to him, surely, I tell thee: Today thou shalt be with Me in Paradise.)
- I am sanctified: Sanctificato sum.
- I walk with God: Ambulo cum Deo. (That is, you follow God's precepts and laws.)
- I am with God: Sum cum Deo. (This is sort of in the sense that you both happen to be in the same room.)
Take your pick.
