That was written by Robert Ingersoll in the late 1800's. You see they had already noticed that there were anachronisms and other unsolvable problems with the Pentateuch's text. Enough problems that many many of the scholars believe Moses did not write it and that possibly Moses was fictitious.<quoted text>Your "author" has no idea if Moses wrote the Pentateuch or not. His "intelligent and honest theologians " are labeled that simply because they have the same liberal agenda.
Higher criticism has found 2 creation stories and 2 flood stories blended together in the Genesis chapter, and then there are the anachronisms of Abraham and Ur of the Chaldee's and the rescue of Lot from the city of Dan, and the list of Edomite Kings that was not known to Moses.
There is also two descriptions of the covenant between God and Abraham. Two stories about the naming of Isaac. Two stories about the renaming of Jacob. Two versions of the Ten commandments. Some refer to God as Yahweh and others as Elohim.
All of this and more comes from the Documentary Hypothesis and is now accepted by essentially all mainline and liberal theologians.
If you add to all of this the fact that the Exodus is a fictional story that kind of leaves Moses in a vacuum. Was he real or not.