If God revelaed God as three distinct persons, then it is easily possible....All things are possible with God.138
Emmanuel is a name of Christ....
God and Christ cannot be one: example: Christ is praying to His Father:
And he went a little further, and fell on his face, and prayed, saying, O my Father, if it be possible, let this cup pass from me: nevertheless not as I will, but as thou wilt.
If one of the three distinct persons of God became a man, then a man may pray to God, and God may reveal His Will to the man.