And as Christ said, "let those among you without sin cast the first stone"

No flesh man is perfect, no not one. It is the simplest concept as well as ultimate futility for someone to hold up another's sin as evidence a permanent disqualifier for the ages. Religion is the very worse caster of stones.

That stone casting action is simply one of the tools of evil, for God truly does forgive.

While flesh David surely was a sinner like we all, he certainly remains as Israels greatest flesh king, establishing the name of David as king forever, yet now, of course, personified by Jesus Christ, David's flesh offspring via a flesh mother, but whose father Is God..

So, indeed David sinned in the flesh, and he paid the price. But after his repentance and God's forgiveness, we find God saying through his Prophet, Nathan,

1 Chr 17:7-24
"Now then, tell my servant David, 'This is what the LORD Almighty says: I took you from the pasture and from following the flock, to be ruler over my people Israel.
I have been with you wherever you have gone, and I have cut off all your enemies from before you. Now I will make your name like the names of the greatest men of the earth.
And I will provide a place for my people Israel and will plant them so that they can have a home of their own and no longer be disturbed. Wicked people will not oppress them anymore, as they did at the beginning and have done ever since the time I appointed leaders over my people Israel. I will also subdue all your enemies. "'I declare to you that the LORD will build a house for you:
When your days are over and you go to be with your fathers, I will raise up your offspring to succeed you, one of your own sons, and I will establish his kingdom.

He is the one who will build a house for me, and I will establish his throne forever.
I will be his father, and he will be my son. I will never take my love away from him, as I took it away from your predecessor.
I will set him over my house and my kingdom forever; his throne will be established forever.'"
Nathan reported to David all the words of this entire revelation.
Then King David went in and sat before the LORD, and he said: "Who am I, O LORD God, and what is my family, that you have brought me this far?
And as if this were not enough in your sight, O God, you have spoken about the future of the house of your servant. You have looked on me as though I were the most exalted of men, O LORD God.
"What more can David say to you for honoring your servant? For you know your servant,
O LORD. For the sake of your servant and according to your will, you have done this great thing and made known all these great promises.
"There is no one like you, O LORD, and there is no God but you, as we have heard with our own ears.
And who is like your people Israel-- the one nation on earth whose God went out to redeem a people for himself, and to make a name for yourself, and to perform great and awesome wonders by driving out nations from before your people, whom you redeemed from Egypt?
You made your people Israel your very own forever, and you, O LORD, have become their God.
"And now, LORD, let the promise you have made concerning your servant and his house be established FOREVER. Do as you promised,
so that it will be established and that your name will be great forever. Then men will say, 'The LORD Almighty, the God over Israel, is Israel's God!' And the house of your servant David will be established before you.

And, of course, Solomon, Davids son did build the PHYSICAL Temple.

But, it was not THAT son, not that physical temple that God was ultimately referring to.

As He prophecied through Ezekiel:

Ezek 34:22-26
Therefore will I save my flock, and they shall no more be a prey; and I will judge between cattle and cattle.
And I will set up one shepherd over them, and he shall feed them, even my servant David; he shall feed them, and he shall be their shepherd.
And I the LORD will be their God, and my servant David a prince among them; I the LORD have spoken it.
And I will make with them a covenant of peace, and will cause the evil beasts to cease out of the land: and they shall dwell safely in the wilderness, and sleep in the woods.
And I will make them and the places round about my hill a blessing; and I will cause the shower to come down in his season; there shall be showers of blessing.

And, of course He began the fulfillment it in the very first verse of the second testament.

Matt 1:1

The book of the generation of Jesus Christ, the son of David, the son of Abraham.(KJV)

and as a second witness,

Luke 1:26-27
26 And in the sixth month the angel Gabriel was sent from God unto a city of Galilee, named Nazareth,
27 To a virgin espoused to a man whose name was Joseph, of the house of David; and the virgin's name was Mary. (KJV)

So, when one sees and hears sounds with their flesh eyes and ears and passes judgement with them, they are surely mistaken.

They are trapped in the forest, seeing only the trees.

When one observes with spiritual senses, the light tend to come on. God's Word is meant to be food for the spirit, and as Christ said to his disciples at the last supper, "Take, and eat ye ALL of it."

It is surely great advice....