'Thousand' in the Bible

So those who accepted his message were baptized, and that day about three thousand people were added.

But many of those who had listened to the message believed, and the number of the men came to about five thousand.

Large numbers of those who had practiced magic collected their books and burned them up in the presence of everyone. When the value of the books was added up, it was found to total fifty thousand silver coins.

Then you're not that Egyptian who started a rebellion and led the four thousand men of the 'Assassins' into the wilderness some time ago?"