I also would like to mention for the Flat Sun theorists, a circle viewed at an angle looks like an oval. If you don't believe me, draw a circle on a peice of paper and tilt it. Ooooh! Its an ellipse now!
The sun is a globe in FE. Its light is limited to a spotlight.
The question, "how is it that the earth is not at all times illuminated all over its surface, seeing that the sun is always several hundred miles above it?" may be answered as follows:--
First, if no atmosphere existed, no doubt the light of the sun would diffuse over the whole earth at once, and alternations of light and darkness could not exist.
Secondly, as the earth is covered with an atmosphere of many miles in depth, the density of which gradually increases downwards to the surface, all the rays of light except those which are vertical, as they enter the upper stratum of air are arrested in their course of diffusion, and by refraction bent downwards towards the earth; as this takes place in all directions round the sun--equally where density and other conditions are equal, and vice versā--the effect is a comparatively distinct disc of sun-light.
Ummm... Dude, light is how we SEE stuff. If the sun was spherical but only emits light like a spot light, than we would still see the oval effect.
The sun emits light in all directions. A sphere at an angle still looks like a sphere, not an oval.
Just to indulge this little overlooked implication, people the sun is passing over don't notice the sun speeding up but in fact see the opposite: slowing down on this straight line.
Chapter 10 of Earth Not a Globe shows how the sun's apparent angle in the sky is not due to perspective, but from its image projected upon the atmosphere. Hence, its speed through the sky is constant. Perspective just describes why the sun sinks as it recedes.
Which is why moving that far towards the horizon would make it appear to shrink massively. Only a very large object would appear to remain constant when moving that far away.
These issues were not covered in your "sacred texts". 
Yes, the issues are addressed. You forgot to read
Chapter 10, which describes how the sun is able to maintain its size at a distance.