The trouble with Hawking and perhaps many other scientists is that they are quite well versed in science but have had no training in philosophy. Not only that, but science can study and observe only that which is material. It cannot study, as a matter of principle, God, angels, the soul, spirit, or anything that is not material. Thus when they think of Creation, they they of it as occurring within a material substrate of space and time. But space and time are part of Creation, not a precondition for it.
I get the impression that when cosmologists and physicists consider the idea of “nothing” they think of it as a substrate of virtual particle and anti-particle pairs. The end result is empty space. But a particle/antiparticle pair can arise spontaneously from such nothingness.
That is not what the theologian means by “nothing.” He means no space, no time, no substrate, no materiality whatever, no potential for materiality, no pre-existing space or time. Pure non-existence of both material and spiritual reality, except for God.