Why do you know so much about the Jews? Did you convert from Judaism?
The answer to this is simple - yet extremely important.
I did not convert from Judaism. Rather, I was blessed to be born into the faith that FULFILLS Judaism.
You see, Judaism and Catholicism are two sides of the same coin. You cannot have one side without the other.
In the Old Testament, God unfolds His plans for humanity. We were created by Him to be part of His family. Much like parents long for children to love and be loved by, God desired a family to love and be loved by. Humanity was the crowning answer to His Love.
Most people view the God of the Old Testament as an angry Zeus-like figure (hurling fireballs at cities or smiting folks for laughs). However, when you really sit down and read through the pages of the OT, you come to learn that far from being an irate and venomous bully, God is a loving, patient Father who repeatedly sets his wayward children back on the path towards their inheritance with Him in Heaven.
Israel, being His "firstborn" (in that the Jews are who He revealed Himself as Father to before any other nation), tended to get the brunt of the "tough love" in an effort to prepare them to act as "big brother" to the other nations who would come to know the Father through them.
However, no one was going to learn about God the Father if the Israelites weren't acting in accordance with God's Will. This is why God punished the Israelites each time they broke their end of the Covenant. God was trying to uphold them as the model of what humanity was supposed to be, but they kept rejecting His Way in lieu of the debauchery that served as the way for their brother nations.
Thus the need for God to constantly step in to remind them, "Hey, Israel... you're supposed to be My Firstborn - My High Priest. You're supposed to be leading people to me through your holy example, not hopping aboard the Sin-Train with them on the way to perdition!"
And if you note His method of punishment, each completely fits the crime. Nothing more, nothing less. Divine Justice is merciful like that. :)
So fast-forward through the centuries. God is always making promises to Israel, reminding them that they've been called to be the gate of graces for the whole of humanity. Through their nation, salvation would be granted to the world in the form of the Messiah. One day, a Christ would come who would fulfill ALL the promises God made to His people in the Old Testament.
The New Testament tells the story of the promised Messiah - a Man called Jesus.
The New Testament is not the foundation for Catholicism... it is the FLOWERING of Judasim (which, in fact, is the foundation of Catholicism).
Look upon the whole of our theology as a tree. The seed was planted by God, Himself, through His covenant with Adam. He nurtured this tree, allowing the roots to take shape through Abraham. The trunk of Israel grew strong, eventually supporting the flowering branches of Christianity. Catholicism, however, is the FRUIT of the tree.
So while I'm not exactly Jewish, I am a sister to the Jews. If not for their millenia of working the theological fields, if not for their many centuries of trying to follow the Will of God, I would not have my Catholicism. I am indebted to the firstborn of God!
Thus, upon my "coming back" to the faith, I made a real attempt to delve into Judaic theology. Only in understanding the Jewish religion can I ever hope to understand my own.
So I hope that answers the question. And as a personal note (because I know you're not Catholic, but some version of Protestant - my apologies for forgetting which), this is true of your faith as well. Christianity stems from Judaism. It's why all Christians keep the Old Testament as well as the New. So understanding Judaism would be beneficial to you just as much (if not more so!).