"In practice no civilized person uses scripture as ultimate authority for moral reasoning. Instead, we pick and choose the nice bits of scripture (like the Sermon on the Mount) and blithely ignore the nasty bits (like the obligation to stone adultresses, execute apostates, and punish the grandchildren of offenders). The God of the Old Testament himself, with his pitilessly vengeful jealousy, his racism, sexism, and terrifying bloodlust, will not be adopted as a literal role model by anybody you or I would wish to know. Yes, /of course/ it is unfair to judge the customs of an earlier era by the enlightened standards of our own. But that is precisely my /point!/ Evidently, we have some alternative source of ultimate moral conviction which overrides scripture when it suits us.
... In practice we, including the religious among us, give [that alternative source of moral conviction] higher priority than scripture."

‏¹ Richard Dawkins, "You Can't Have It Both Ways: Irreconcilable Differences?", Skeptical Inquirer, Vol. 23 No. 4.
‏² Stephen Jay Gould, "Non-Overlapping Magisteria", Leonardo's Mountain of Clams and the Diet of Worms, Harmony Books, 1998; reprinted in Skeptical Inquirer, Vol. 23 No. 4.