Impossible to find salvation through the law because of the weakness of the flesh. And you switched from your argument of the law to faith. Of course the law is a schoolmaster to lead us to Christ.
Faith and Law are not mutually exclusive concepts. In fact, for any NC believer the two are perfectly consistent with each other; for the believer knows that he cannot be saved by obeying the law absent any faith! Christians love God's law because they handle the law correctly. They want to obey the Law because they love the Lord and trust him -- and not because they are trying to win God's favor. By God's grace, I have the same attitude towards God holy Law as the Psalmist does in Ps 119, for example.