Paul is in the wrong boat then, too:
"Then what [a]advantage has the Jew? Or what is the benefit of circumcision? 2 Great in every respect. First of all, that they were entrusted with the oracles of God. " Rom. 3:1-2 (NASB)
I am aware that the Jews rejected Christ, but that doesn’t mean that they were wrong about everything. Obviously both Protestants and Catholics use Jewish books.
I am aware that many of the citations in the NT are from the LXX. However, I don’t see how that proves the Deuterocanonicals are Scripture, as the Deuterocanonicals were not considered Scripture in the LXX. I would love to see a source that proves otherwise. You are basing your argument off of inference.
Paul goes on to say:
9 What then? Are we Jews any better off?[a] No, not at all; for I** have already charged that all men, both Jews and Greeks, are under the power of sin, 10 as it is written:
“None is righteous, no, not one;
11 no one understands, no one seeks for God.
12 All have turned aside, together they have gone wrong;
no one does good, not even one.”
13 “Their throat is an open grave,
they use their tongues to deceive.”
“The venom of asps is under their lips.”
14 “Their mouth is full of curses and bitterness.”
15 “Their feet are swift to shed blood,
16 in their paths are ruin and misery,
17 and the way of peace they do not know.”
So going by the opinion of Jews according to the flesh ultimately doesn’t serve you well, because they are still under the power of sin.
And as to your second claim, here are the words of Clement and Polycarp, both contemporaries of Peter and John:
Clement
“By the word of his might [God] established all things, and by his word he can overthrow them. ‘Who shall say to him, “What have you done?” or who shall resist the power of his strength?’ [Wis. 12:12]” (Epistle to the Corinthians 27:5 [ca. A.D. 80]).
Polycarp
“Stand fast, therefore, in these things, and follow the example of the Lord, being firm and unchangeable in the faith, loving the brotherhood [1 Pet. 2:17]. . . . When you can do good, defer it not, because ‘alms delivers from death’ [Tob. 4:10, 12:9]. Be all of you subject to one another [1 Pet. 5:5], having your conduct blameless among the Gentiles [1 Pet. 2:12], and the Lord may not be blasphemed through you. But woe to him by whom the name of the Lord is blasphemed [Isa 52:5]!” (Epistle to the Philadelphians 10 [ca. A.D. 135]).**