"In my paper, I suggested that the lack of a "material" cause is at last as counter-intuitive as the lack of an "efficient" cause. Craig's response is interesting. There are, he says, just three possibilities with respect to the origin of the universe: "the infinitude of the past, creation ex nihilo, [and] spontaneous origination ex nihilo." Assuming (as we have agreed to do for the sake of argument) that Craig's philosophical arguments against the infinite past are sound, we must choose between creation ex nihilo and uncaused origination ex nihilo. Craig says he prefers the creation hypothesis, since it involves only one counter-intuitive element, whereas the spontaneous origination hypothesis "is doubly counter-intuitive in that it denies of the universe both a material and (especially) an efficient cause.". . .[T]here is a serious gap in Craig's argument for creation ex nihilo, since the trilemma -- either the infinite past, or creation ex nihilo, or spontaneous origination ex nihilo -- fails to exhaust the logical alternatives. There is at least one other possibility that Craig fails to consider -- viz., that God made the world out of something-or-other that is (or "was") eternal.
I confess that I do not have a candidate for a material cause of the universe. . .we don't seem to be acquainted with any. . .eternal "stuffs" out of which God might have made the universe. But that shouldn't stop Craig. We don't encounter eternal persons either, but he thinks his commitment to P1 [i.e., the premise that everything that begins to exist has a cause of its existence. -EA] forces him to postulate one. Why, then, does he not simply conclude that there must have been an eternal material cause, on the ground that he can thereby avoid, not only the "double absurdity" of spontaneous generation, but also the "single absurdity" of creation ex nihilo?"
Morriston, Wes. "Causes and Beginnings in the Kalam Argument: Reply to Craig", Faith & Philosophy 19:2 (2002), pp. 238-239.