During a time when it seems that critics of the Bible are on the rise, what a terrific question such as the one before us! Paul, writting to Timothy, stated: "All scripture is given by inspiration of God, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness" (2 Tm. 3:16). As a result, we are dealing with the word of God and not the words of men (1 Th. 2:13). When we are dealing with what the Bible says, we are dealing with truth (Jn. 17:17).
Any honest reader of the Bible will be forced to conclude, upon examining what the Scriptures say, the days of Genesis 1 and 2 are literal, 24 hour days, as we have today.
"In the beginning God created the heaven and the earth" (Gn. 1:1) is how the Sacred Volume begins. We are not here by chance or mere accident and are certainly not the product of evolutionary processes. We are here because God created us and did so in His own image (Gn. 1:26).
In Genesis 1:5 we read "And God called the light Day, and the darkness he called Night. And the evening and the morning were the first day." Throughout the verses following, we read the phrase "And the morning and the evening were...." It is completely illogical for one to read these statements and conclude it was millions or billions of years. Especially in light of the fact that the pursopse of the "lights" being created in the firmamament of heaven was for them to "divide the day from the night; and let them be for signs, and for seasons, and for days, and years" (v. 14). Upon creating the sun, moon, and stars, it is stated in verse 18: "And to rule over the day and over the night, and to divide the light from the darkness: and God saw that it was good."
Notice what is stated in Exodus 20:11, "For in six days the Lord made heaven and earth, the sea, and all that in them is, and rested the seventh day: wherefore the Lord bliessed the sabbath day, and hallowed it." Had the Jews not known what constituted a "day" how could they have possibly known when to observe the Sabbath Day? If days represented vast eons of time, how could they have known when the Sabbath Day arrived?
The days of Genesis 1 and 2 are literal, 24 hour days. Thanks be to God for his infaliible Word!