IS THE LAW PERFECT OR NOT ?

Psalms 19:7. The law of the Lord is perfect, converting the soul: the testimony of the Lord is sure, making wise the simple. (KJV) Hebrews 8:6-8 But now hath he obtained a more excellent ministry, by how much also he is the mediator of a better covenant, which was established upon better promises.  For if that first covenant had been faultless, then should no place have been sought for the second. (KJV)

The mistake critics make her is assuming that the 'law' and the 'covenant' are the same thing.  They're not.  The covenant was the agreement the Israelites made to follow the law.  Since they were unable to follow it perfectly, a second covenant was made, one in which Jesus' following of the law allowed Him to die in our place.  Not a contradiction.