There’s a longer explanation, but this needs to be put out where it can be caught by search engines.

Benjamin Franklin reading the Pennsylvania Gazette, or “Ben on the Bench” (with a bird), statue at the University of Pennsylvania – photo via Priyank
This is the 51st chapter of the Book of Genesis, as related by Benjamin Franklin. This copy of the text comes from a newspaper, The Otago Witness, December 2, 1887, page 35, courtesy of a website called Papers Past, maintained by the National Library of New Zealand.
Paste It in Your Bible.
A Chapter Verily Like the Original— How Benjamin Franklin Surprised Ms Friends.
Over 100 years ago the following so-called “Genesis 51” was used to puzzle Biblical scholars, and today, were it read aloud in any mixed company, it is questionable if its fraudulent nature would be discovered, so beautifully is the spirit and language of the Old Testament imitated : —
1. And it came to pass after these things, that Abraham sat in the door of his tent, about the going down of the sun.
2. And behold a man, bowed with age, came from the way of the wilderness leaning on a staff.
3. And Abraham arose and met him, and said unto him, Turn in, I pray thee, and wash thy feet, and tarry all night, and thou shalt arise early on the morrow, and go thy way.
4. But the man said, Nay, for I will abide under this tree.
5. And Abraham pressed him greatly; so he turned, and they went into the tent, and Abraham baked unleavened bread, and they did eat.
6. And when Abraham saw that the man blessed not God, he said unto him, Wherefore does thou not worship the most high God, Creator of heaven and earth?
7. And the man answered and said, I do not worship the God thou speakest of, neither do I call upon his name; for I have made to myself a God which abideth always in my house and provideth me with all things.
8. And Abraham’s zeal was kindled against the man, and he arose and drove him forth with blows into the wilderness.
9. And at midnight God called unto Abraham, saying, Abraham, where is the stranger?
10. And Abraham answered and said, Lord, he would not worship Thee, neither would he call upon Thy name, therefore have I driven him out from before my face into the wilderness.
11. And God said, Have I not borne with him these hundred and ninety and eight years, and nourished him, and clothed him notwithstanding his rebellion against me, and couldst not thou, that art thyself a sinner, bear with him one night ?
12. And Abraham said. Let not the anger of my Lord wax against His servant; lo! I have sinned, forgive me, I pray thee.
13. And Abraham arose and went forth into the wilderness, and sought diligently for the man, and found him and returned with him to the tent, and when he had entreated him kindly, he sent him away on the morrow with gifts.
14, And God spake again unto Abraham, saying, For this thy sin shall thy seed be afflicted four hundred years in a strange land.
15. But for thy repentance will I deliver them, and they shall come forth with power, and with gladness of heart, and with much substance.
In 1759, when in England as agent for the colony of Pennsylvania, Benjamin Franklin privately printed this “Chapter,” as he always termed it. Taking only a sheet of paper, he kept it laid in his Bible at the end of Genesis, and used to amuse himself by reading it aloud to his friends, and hearing them express their surprise that they had never recollected reading it, and their openly expressed admiration of the moral it carried with it. Its origin is unknown. It has been traced back 700 years to a Persian poet, who simply says “it was so related.” It must be very old.
Ben Franklin’s version of Chapter 51 of the Book of Genesis is a hoax. There is no such chapter.