How could Abraham dine with God? How could Abraham have possibly dined physically with God as suggested in Genesis 18, especially when &quot;No one has ever seen Him&quot;?

1 Timothy 6:16
He alone is immortal and dwells in unapproachable light. No one has ever seen Him, nor can anyone see Him. To Him be honour and eternal dominion! Amen.
Genesis 18:1-8
The Lord appeared to Abraham near the great trees of Mamre while he was sitting at the entrance to his tent in the heat of the day. 2 Abraham looked up and saw three men standing nearby. When he saw them, he hurried from the entrance of his tent to meet them and bowed low to the ground.
3 He said, “If I have found favor in your eyes, my lord,[a] do not pass your servant by. 4 Let a little water be brought, and then you may all wash your feet and rest under this tree. 5 Let me get you something to eat, so you can be refreshed and then go on your way—now that you have come to your servant.”
“Very well,” they answered, “do as you say.”
6 So Abraham hurried into the tent to Sarah. “Quick,” he said, “get three seahs[b] of the finest flour and knead it and bake some bread.”
7 Then he ran to the herd and selected a choice, tender calf and gave it to a servant, who hurried to prepare it. 8 He then brought some curds and milk and the calf that had been prepared, and set these before them. While they ate, he stood near them under a tree.
How could Abraham have possibly dined physically with God as suggested
  in Genesis 18, especially when "No one has ever seen Him"?


My understanding something like this (my own Trinitarian version).

Before incarnation, all the 3 person of Trinity has one name which is in that time the name is called Yahweh.

After incarnation, all the 3 person of Trinity has one name which is in that time the name is called Jesus.

The First Person will never be seen by human because the world won't be able to contain it, while The Second Person is every event when human see Him in a "limited" state.



1 Timothy 6:16 and John 6:46 is speaking about Jesus the Father (First Person)

Genesis 18:1-8 (and maybe some other verses) is speaking about Yahweh the Son (Second Person).

I'm not sure though :).