How do we know the covenant of works is insufficient?

The covenant of works demands absolute perfection and continual obedience to the law, as outlined in Galatians 3:10, which states that anyone relying on the law for justification is under a curse, as none can keep the law perfectly. Paul illustrates that the law's inability to save reveals its true purpose: to expose sin and our inability to achieve righteousness on our own. This underscores the necessity of the covenant of grace, where Christ fulfills the law on behalf of believers, providing a way to be justified apart from works.