at first I considered all the texts and propers separately - all are tremendous treasures in their own right. I didn't see any connection until Luther's Writing ("Thus the incarnation and the death of Christ are both comprehended most concisely in this one word, 'testament.'" WOW!) reminded me to see today's Words from TDP united in Christ.
The heir to David's throne is privately plotted against by those who would usurp his authority thinking the Father is unaware of their schemes (1 Kings 1). Adonijah assumes that if he is not the head, he is nothing (1 Corinthians 12:15-16). Yet, as head, he would say "I have no need of you" (1 Corinthians 12:21) to Solomon and Bathsheba (1 Kings 1:21) - and probably Nathan, Zadok, and Benaiah as well! (Now hear the Pharisees and Sadducees and Romans saying this to Jesus!)
A lot is at stake here if Adonijah succeeds - both the faith of Israel in rejecting Nathan and Zadok, but also your salvation which is found in the descendant of Solomon!
God leads David in the way everlasting (Psalm 139:24) - despite what David deserves for his secretly usurping Uriah's role, despite what we deserve for our "usurpations." Adonijah (and the Pharisees, Saducees, and Romans - and atheists and synergistic pagans of our day) will not succeed. The son of David will be the Head. Jesus is risen from the dead, putting to death the plots against Him.
And now you have your role in His body (1 Corinthians 12:27-31). Do not say "Because I am not as brainy/witty/popular/well-spoken as so-and-so, I do not belong to the body." In His book were written all your days and the important roles you would play in the body of Christ when as yet there were no days. Wonderful are His works indeed (Psalm 139:14-16).