Sometimes parents are lazy. Has there ever been a time when your child wanted to do something but it just wasn't a good time? I can't imagine any parent who has not experienced that. Suppose your child wanted to go to the zoo, for example. You could explain that you have too many other things to do, you just went recently anyway, it's too hot today, another time would be more enjoyable, etc. Even if the reasons you don't want to go are all reasonable, children are often not satisfied. The solution for some parents is to say, “The zoo is closed.” It may be a lie but it works. Kids understand that you can't go somewhere when it's closed so that will usually end the discussion. A lie can accomplish what reasoning couldn't.
We resort to this tactic because we are human and humans lie. It's part of our sin nature. We can try to justify it any way that we want but it's a lie and that's all there is to it. What amazes me is that many people who profess to be Christians, accuse God of using this tactic in describing the creation account in Genesis. Read how one old-earth creationist describes this (source):
If God's creation was billions of years old, how would He have written the creation account in Genesis? One thing is certain...God is good at telling us exactly what we need to know. ¶When God refers to a large number, He uses picture stories, such as Abraham's descendants being as numerous as the sand. Why does He do this? If God had said, "You will have millions of descendants," Abraham would have asked, "What is a million?" ¶When considering the creation, if we broke it down into days, that would be 5,000,500,000,000 days, or roughly 13.7 billion years. Do we need an account for each day of creation...of course not. God in His infinite wisdom, saw fit to tell us the creation story by breaking it down into creative segments, each of which was attributed to a specific creative act or acts. We need to give the early Hebrews of Genesis a break...they didn't have calculators like we do! [ellipses in original]
This author's point is that the ancients would not have been able to grasp the concept of millions or billions of years. He claims that God, “in His infinite wisdom,” chose to reveal the creation in terms the people could understand and so He broke it down into days. The author is saying, in a sense, God chose the “the zoo is closed” solution.
I have several problems with this explanation. First, it casts aspersion on the intelligence of the ancients. I know that we have discovered many things that the ancient Hebrews did not know but, even so, they were not imbeciles. Children, with their immature minds, might not be able to understand the abstract. You can't tell a child that “a million” is the same as “a thousand thousands” because children don't understand what a thousand is either. However, I'm sure that an adult Jew, even in 2000BC, could understand large numbers if they were explained to him.
Such a solution also casts aspersion on the intelligence of God. Knowing that God is infinitely wise, as this author claims to believe, could He have not explained the creation in such a way that even the unscientific Hebrews would understand? I would direct you to the numerous examples in the New Testament, where Jesus was quite capable of explaining deep spiritual truths in terms that people could understand. He used parable, simile, and metaphor but it was always clear that He was doing so. If the creation were billions of years, God could have easily said, “The days of the creation are like the grains of sand in the sea. No one can number them.” Note the use of the word “like” denoting simile. It's absurd to believe that God lacked the ability to explain the creation without resorting to fairy tales.
This brings me to my final point. Such a solution casts aspersion on the character of God. The parent who tells his child the zoo is closed is a liar. That's no surprise because we are sinners and we lie. God, however, cannot lie. If God created the world over billions of years but said He did it in six days, then He would be lying! Like the lazy parent who knows saying the zoo is closed is the easiest way to tell his child they're not going to the zoo, to claim that God chose a 6 day creation story because it was the easiest way to tell His children about the creation is to call God a liar!
The ancients were not children. God is not stupid. God does not lie. If God had created the universe over billions of years, He would have told us that. He did not have to say “six days.” He didn't have to resort to “the zoo is closed.”