Sin makes you stupid.
Why did The Lord not accpet King David’s perfect contrition?
Why did The Lord not forgive David?
He did, but sins also require a temporal punishment. Let’s not forget that David directly violated two of the Ten Commandments, and he was supposed to be the leader of the Chosen People.
Why did The Lord kill King Davids child instead of Punishing King David?
I believe that later on, David talks about being reunited with the child in the afterlife. So perhaps the child was taken directly to “Abraham’s bosom” rather than having to grow up and deal with the entire civil war involving Absalom, etc…
Does The Lord become pro choice after killing a innocent baby?
The Author of Life also has the sovereign right to take a life according to the demands of His justice.
Why is King David not a Saint or Prophet?
He certainly is a prophet - look at some of the Psalms. Besides, in the Hebrew Bible, the books dealing with David are also considered to be prophetic (1 & 2 Samuel and 1 & 2 Kings - or 1-4 Kings if you use the Vulgate.)
Should we respect King David Today after his terrible sin?
Of course. He repented, fasted, and took his punishment like a man. More than I can say for most contemporary world leaders.
Thanks for answering all these questions as I do not know the answers.