As the Bible implies, there
WAS a delay in the appearance of light. The scientific facts support this, because
all the matter in the heavens was in the Plasma State.
This meant that electrons were decoupled from the nucleus of the
atoms because of the hot the high energy states.
Light can only come from electrons when the are part
of Atoms.
Note, in the picture of the Big Bang above, that seven (7) stages of development followed the initial
Big Bang.
During the 5th Stage, electrons coupled up with the nuclei
to form the first actual Atoms.
After 300,000 years, light finally appeared in the Universe.