Atheists and agnostics frequently assert that ethics and morality are not dependent upon a belief in God. Rather, they urge that ethics and morality can be understood in sociological terms as a set of conventions that provides evolutionary advantage for groups of humans. But the true weight of such an assertion is rarely grasped by those who make it. This is not an alternative morality, but really no morality at all.
This is pointed out with wit by Dr. William Lane Craig.
The point is that a meaningful morality, a genuine belief in “right and wrong,” requires a faith commitment to something beyond the “here and now,” that is, it requires something “metaphysical.” And of course, the only consistent morality, one that can bear the weight of its own assertions, is the morality revealed in the Christian Scriptures by the one true God.