One might wonder why we can talk about the universe expanding in time given that GR is based on SR: given relativity’s challenge to the idea of ‘the present’, how can there be a unique ‘present’ which defines ‘the universe’ and allows it to be described as an ‘object’ expanding in time? The answer involves two facts: 1) The mathematical equations of GR can be factored into a ‘space plus time’ form, i.e., a 3-geometry whose characteristic size is a function of time, if the distribution of matter in the 3-geometry is uniform. 2)Hubble’s observations show that, at large enough distances, galaxies at the same distance are uniformly distributed in space. One can appeal to this idea theologically by claiming that the ‘present’ of the universe which God experiences is defined by its uniform mass distribution and expansion in time. However, it should be kept in mind that the underlying equations of GR are even more complex than those of SR, and the distinctive meaning of space and of time in GR is correspondingly more problemmatic. See for example Chris J. Isham, "Quantum Theories of the Creation of the Universe," in Quantum Cosmology and the Laws of Nature: Scientific Perspectives on Divine Action, ed. Robert J. Russell, Nancey C. Murphy and Chris J. Isham, Scientific Perspectives on Divine Action Series (Vatican City State; Berkeley, Calif.: Vatican Observatory Publications; Center for Theology and the Natural Sciences, 1993), Section 3; Drees, Beyond the big bang, Appendix 5.