Time relativity in the Quran
The Quran says that a day of the Lord is like a thousand years of what we count. Some propagandists of "miracles in the Quran" are claiming that this means that the author of the Quran knew about Einstein's relativity and therefore the author of the Quran could not be Muhammad who lived 1400 years ago.
And they urge you to hasten the punishment. But Allah will never fail in His promise. And indeed, a day with your Lord is like a thousand years of those which you count.
One does not have to understand the theory of relativity to come with such verse. He could just think about god, how he must see everything on a bigger scale.
Besides that, similar content was in the Old Testament and Muhammad could have been inspired by it:
A prayer of Moses the man of God.
Lord, you have been our dwelling place throughout all generations.
Before the mountains were born or you brought forth the earth and the world, from everlasting to everlasting you are God.
You turn men back to dust, saying, "Return to dust, O sons of men."For a thousand years in your sight are like a day that has just gone by, or like a watch in the night.
If this is a miracle, then it is a miracle of the Bible and not of the Quran, because the Bible mentioned it first.