However, we often make the distinction between believing in God and believing God. We know it is good to believe in Him, but better to believe Him. Self-described agnostics and atheists that follow God's principles and commandments are on a good path. Though missing an important belief, they are showing by their actions that they believe God even if they do not believe he exists (or are unsure). Even when missing a strong belief in the existence of God, a child of God can still exercise faith in His teachings.
The argument might be made that atheists and agnostics are choosing to do good of their own will, and not out of any respect for God. Though their actions do stem from their own will, it is impossible for a person to act unless he or she is enticed by good or evil. All good comes from God, so when a person is enticed to do good, the origin of that enticement can ultimately be traced back to God Himself. Atheists and agnostics may deny that their enticement to be faithful came from God, but they can't prove it does not. They simply accept it on faith--false faith, in this case.
We shouldn't be quick to condemn atheists and agnostics. They may lack a critical belief, but in many cases we may discover that they are more faithful than many who do profess a belief in God.