The Widow's Son
When our Grand Master Hiram Abiff was confronted by three ruffians as King Salomon's temple was nearing completion, they demanded the secrets of a Master Mason. Knowing the kind of man that he was, I doubt that he was as concerned with his own safety and life as he was with the lives of those three ruffians, knowing that if they were the kind of men that would attempt to extort those secrets from him ,then they were not the kind of men for whom those secrets would have any value. Paul, in his first letter to the Corinthian saints echoed this sentiment when he said:
But the natural man receiveth not the things of the Spirit of God: for they are foolishness unto him: neither can he know them, because they are spiritually discerned. 1 Corinthians 2:14
In order to understand the value of any system of morality, you need the assistance of a higher power. Joseph Smith was admonished:
And the Spirit shall be given unto you by the prayer of faith; and if ye receive not the Spirit ye shall not teach. D&C 42: 14
This is the reason that no atheist can be made a Mason, for without a belief in a higher power, no obligation would be binding, or taken seriously.