When Moses tried to relieve the oppression of the Israelites on his own strength forty years before, nothing happened. He ran to do the work of the Lord, but God was not in it. The point that God is making is that, no matter how sincere a person is, if he is not tuned into the will of God, even though he does a great work and is noble and pure of heart, real success comes from God because God is in it - not due to the efforts of the man. The result then was a sincere effort but futile. Moses created a stir, but it was ineffective because God was not in it. It was not His will. It did not become His will until forty years later.
What happened to Moses in the intervening years was that he was truly humbled and converted. He had given himself to God to such an extent that he was almost afraid to move, and God had to bring him back a way to restore some of his initiative. However, now that initiative would be used in harmony with a strong relationship with Him. Since Moses truly had the fear of God, he took God into account in every action. That is what the fear of God does to a person: It makes a person consider God and His desires in everything that he does.
Moses grew to know God so well that he could interpret God's mind as few men ever could. Many people have strong beliefs, but are they right? Are they in harmony with God's will? A belief must not only be strong, but it must also be right. It is proved right in the process of living: Righteous actions will produce godly fruit. This is why Jesus says, "You will know them by their fruits" (Matthew 7:16). The fruits of a person's life will show what a person believes, producing in him a resolution that his actions are God-ordered and he dare not turn aside or change them.
Are we living what we believe?