Rev 22:1,3 "...the throne of Yahuweh and the Lamb"

How many are sitting on the Almigthy's throne?

Years ago while traveling across the U.S. I was asked to stop at a fellow's house in Illinois  to discuss the subject of the Trinity with him. If I remember correctly I think the first question he asked me was, in the most pious tone that I had heard in quite a while, "have you ever considered how big the Almighty's throne is?"  I had to confess I never really thought about the size of it, so I had to humbly admit, "no, I can't say that I ever did."   So he went on to explain to me, "since there are 3 that make up the Trinity they must each  have a throne, or perhaps it's just one big throne that the 3 of them share."  

Now, I understood the reason for his question. Since, as he believed, there were 3 gods, and yet actually only one, it's called the mystery of the Trinity, how big would the throne have to be to accommodate all 3 of them.  

I asked him if he would to turn to 1 Chronicles 29:23  where it says,  "Then Solomon sat on the throne of Yahuweh as king instead of David his father, and prospered; and all Israel obeyed him."
I  then asked him, somewhat facetiously, "now that we see Solomon is sitting on the throne also do you think they might have had to make it a 4-seated throne, Father, Son, Holy Ghost and Solomon?"  Since he wasn't answering I went on to explain to him why Solomon is said to be sitting on the Almighty's throne.

Solomon is said to be 'sitting on Yahuweh’s  throne,'  because he was Yahuweh's representative, ruling over Yahuweh’s people, Israel.

In  2 Chronicles chapter 9, the Queen of Sheba, realized that even though Solomon sat upon the Throne of Yahuweh, this did not make him, Solomon, any more part of 3 in 1 god, then it makes the Messiah, Yahoshua, part of a Trinity     
2 Chronicles 9:8    "Blessed be Yahuweh thy God, which delighted in you to set you on his throne, to be king for Yahuweh thy God: because thy God loved Israel, to establish them for ever,..."

You see this fellow was confused in thinking that since we're told that Yahoshua the Messiah will sit on the Almighty's throne, somehow Yahoshua must be the Almighty.  Of course it was his lack of understating of the Scriptures that caused him to come away with such an unscriptural idea as to think there are 2 or 3 Almighty's.  

The simply truth is that since Yahoshua, as Solomon and David before him, will soon take his rightful place ruling over Yahuweh's people, it can be said that he is sitting on Yahuweh's throne.

Zech 6:12-13,  , "...Thus says Yahuweh of hosts, Behold the man whose name is The BRANCH (see Jer 23:5-6); and he shall grow up out of his place, and he shall build the temple of Yahuweh:  Even he shall build the temple of Yahuweh; and he shall bear the glory, and shall sit and rule upon his throne; and he shall be a priest (see Heb 7:17) upon his throne..."

Even 'WE' believers, that overcome, as the Messiah overcame, will sit on the  throne with the Messiah, meaning we, if we attain to that spiritual height, will rule and reign with Messiah (Rev 5:10).
                                                                   
Rev 3:21,  To him that overcomes will I grant to sit with me on my throne, even as I also overcame, and am set down with my Father in his throne.

Yahoshua, right now, is sitting at the right hand of the Father, and someday very soon, I believe, he will be ruling and reigning over Yahuweh's people Israel (Ps 110:1).

So again, because it is said that the Messiah, Yahshua, 'sat upon the throne of Yahuweh,' to rule over Yahuweh's people, that does not make Him part of a 3 in 1 god, any more than it did for Solomon or as it will for us.