How do we know that perfect obedience is required by God?

The Sermon emphasizes that the only obedience recognized by God is perfect obedience, which is delineated through God's commandments. For example, the Ten Commandments reflect an absolute standard—breaking even one commandment constitutes disobedience. In James 2:10, we see that failing in one part of the law makes one guilty of all. Therefore, God's expectation is not that we simply try to obey but that we uphold His commandments perfectly. Romans 3:23 reminds us that all have sinned and fall short of His glory, illustrating our desperate need for Christ's righteousness.