Christ, for one, had to abide by the law and he never taught that the Torah was wrong; he simply taught that some interpreted it wrongly. He also never taught that we are saved by faith alone. If anything, he emphasizes works.
+Paul on his part kept the law as well. He just didn't hold the non-Jews to it. Being a Jew he was acutely aware that only Jews are obligated by the law, but God's choice, and that holding Gentiles to it would be contrary to God's wishes because God never says non-Jews fall under the law.
Being clever, +Paul understood that the law by itself doesn't save, but only God's grace. That's why he says
We are all equally guilty! We all have sinned. We are not saved by the law, nor by faith, but by God's mercy.
However, if that's the case, why keep any commandments? The answer, of course, is out of love. When the Orthodox go to confess, they say
We don't say that we have broken the law. We didn't break the law. We did something much worse: we "dumped" God for something material and passing, for the love of the world, for the love of Mammon over God, out of disrespect for the One who gave us everything, including our life.
And if that is the case, "Christ shall profit you nothing...[and] ye are fallen from grace." (5:2,4)
The Bible also says that God will save whomever he wants to save.
As for the Law, +James—Paul's nemesis—teaches
You can't only quote +Paul. There is other talent besides him. :)
I don't see Christ anywhere suggesting one is saved by faith alone. Nor do I see anywhere Christ calling on ministering to the Gentiles by dropping the Law. He only places love as the motivator as the reason for obeying commandments, and not the law itself. In other words, obey the commandments our of respect for, and gratitude to God, and not because "it's the law."
If you love God with all your heart and mind and soul, you will not have to worry too much about breaking the commandments.
"Owe no man any thing, but to love one another: for he that loveth another hath fulfilled the law. For this, Thou shalt not commit adultery, Thou shalt not kill, Thou shalt not steal, Thou shalt not bear false witness, Thou shalt not covet; and if there be any other commandment, it is briefly comprehended in this saying, namely, Thou shalt love thy neighbour as thyself. Love worketh no ill to his neighbour: therefore love is the fulfilling of the law." (Romans 13:8-10).
And to quote someone besides St. Paul :) and clarify him:
And hereby we do know that we know him, if we keep his commandments. He that saith, I know him, and keepeth not his commandments, is a liar, and the truth is not in him. But whoso keepeth his word, in him verily is the love of God perfected: hereby know we that we are in him."(I John 2:3-5).
And to quote your favorite ;-)
"Once for all, then, a short precept is given thee: Love, and do what thou wilt... of this root can nothing spring but what is good." St. Augustine (In epistulam Ioannis ad Parthos)