The Gap theory adds in billions of years into the bible between the first and second day of creation. This “gap” is adds eons of time not required by the miracle of creation by an all powerful God, but rather as required to have the text meet the evolutionary theories of man.
If the gap theory is used to ‘save’ evolutionary timelines of millions and millions of years to match man’s opinion of the age of the universe it fails in many areas. Consider the order of creation, it makes no sense. Consider the earth created before the stars. Plants were created before the sun. How could plants survive a million years without the energy of the sun? Where would you fit all the millions of years demanded by evolution? Also, even millions of years between events (also as in progressive or theistic evolutionary perspectives) falls billions of years short of evolutionary timescales. Evolutionists know these facts and consider such revisions of the biblical text as nonsensical.
If by contrast, the gap theory, progressive creation, or theistic evolution are used to ‘save’ the biblical text it also fails. A simple reading of the bible reveals the intention is God created everything in six days and rested on the seventh day. Literal days. First, the meaning of the word day “yom” in Hebrew when used in conjunction of “an evening and a morning” as described during each day of creation in Genesis, always means a single ordinary day. Second, the ten commandments include keeping The Sabbath. This is defined as working six days and resting on the seventh day, God explains, just as He created the heavens and the earth in six days and rested on the seventh—so we should honor this as well. Third, the word “day” is used in the bible over 2,300 times but its meaning is only questioned during creation week.