James 2:10
For whosoever shall keep the whole law, and yet offend in one point, he is guilty of all.
The only person in all of human history who's ever "kept the law" perfectly is Jesus Christ. And unless you keep the law perfectly, you don't keep the law at all. So where is boasting?
Boasting of having faith and not keeping the law doesn’t sound quite right either. Biblically, a faith that is alive is required. And faith without works is dead.
Only faith, but not dead faith.
Who(m) is boasting? I am to keep the whole Law. I do my best to keep the whole Law. And in my deficiency His Grace suffices. But if I let Him control my thoughts and deeds I have kept the law to my ability. No boasting on my part.