Ok. I understand your point now. Thanks for clarifying.

Your understanding has at least one thing wrong with it. It presupposes that Timothy not being circumsized even though he was a spirit filled believer in Jesus who was intimately acquanted with the Torah and the Prophets (scripture) is the same reason the whole nation of Israel didnt get circumsized, who didn't have a personal/internal relationship with the Messiah.

That is speculation and an unfounded correlation.

However, Paul gives a clear reason as to why he would circumsise Timothy. He did it to not be a stumbling block to the Jews he was ministering to.

Acts 16
1 Then came he to Derbe and Lystra: and, behold, a certain disciple was there, named Timotheus, the son of a certain woman, which was a Jewess, and believed; but his father was a Greek:
2 Which was well reported of by the brethren that were at Lystra and Iconium.
3 Him would Paul have to go forth with him; and took and circumcised him because of the Jews which were in those quarters: for they knew all that his father was a Greek.
4 And as they went through the cities, they delivered them the decrees for to keep, that were ordained of the apostles and elders which were at Jerusalem.
5 And so were the churches established in the faith, and increased in number daily.

Right from that context we can see that he circumsized Timothy because of the Jews in those quarters because they (the Jews) knew his father was a Greek. He didn't do it because he wanted Timothy to be obedient to the Torah. He did it because of the Jews and their knowledge of Timothy's possible uncircumcision.

Contrast this reason with when Paul refused to circumsize Titus:

3 But neither Titus, who was with me, being a Greek, was compelled to be circumcised:
4 And that because of false brethren unawares brought in, who came in privily to spy out our liberty which we have in Christ Jesus, that they might bring us into bondage:
5 To whom we gave place by subjection, no, not for an hour; that the truth of the gospel might continue with you. Galatians 2:3-5

Notice that these were false brothers. They were the Circumcision Party, also known as the Circumcision and the Consision. They weren't unbelieving Jews who needed to be evangelized. These were Jews who had been evangelized yet we're now teaching that Circumcision and keeping the Law of Moses must be done to be saved ( saved is in the future tense, meaning at the resurrection.)

Understanding this helps us understand why Paul circumsized Timothy, but refused to circumsize Titus.

He further clarifies why he circumsized Timothy here:

18 What is my reward then? Verily that, when I preach the gospel, I may make the gospel of Christ without charge, that I abuse not my power in the gospel.
19 For though I be free from all men, yet have I made myself servant unto all, that I might gain the more.
20 And unto the Jews I became as a Jew, that I might gain the Jews; to them that are under the law, as under the law, that I might gain them that are under the law;
21 To them that are without law, as without law, (being not without law to God, but under the law to Christ,) that I might gain them that are without law.
22 To the weak became I as weak, that I might gain the weak: I am made all things to all men, that I might by all means save some.
23 And this I do for the gospel's sake, that I might be partaker thereof with you.
1 Corinthians 9:18-23.

This clearly explains why Paul circumsized Timothy. Not because he believed it was still necessary, because he clearly didn't believe that, otherwise he would have circumsized Titus and wouldn't have told the Galatians and the Corinthians to not get circumsized.