Jasher is not a persons name. It's not like "The Book of Ruth" or "The Book of Esther." It's not a letter written by a man named Jasher, such as 1Peter. The word "Jasher" means "upright." It is, therefore, The Book of the Upright.
The Book of Jasher is a history book written over 3500 years ago; approximately the same age as the Book of Genesis. It clarifies and expounds on the Books of Moses--Genesis through Deuteronomy--as well as The Book Of Joshua. It is mentioned several times in the canonized Holy Bible:
“Sun, stand still over Gibeon,
and you, moon, over the Valley of Aijalon.”
So the sun stood still,
and the moon stopped,
till the nation avenged itself on its enemies,
as it is written in the Book of Jashar (Joshua 10:13 NIV).
David took up this lament concerning Saul and his son Jonathan, and he ordered that the people of Judah be taught this lament of the bow (it is written in the Book of Jashar):
“A gazelle lies slain on your heights, Israel.
How the mighty have fallen! (2 Samuel 1: 17-19).
Just as Jannes and Jambres opposed Moses, so also these teachers oppose the truth. They are men of depraved minds, who, as far as the faith is concerned, are rejected (2 Timothy 3:8).
While this last verse does not mention "Jasher/Jashar" by title, it mentions an incident from the book of Exodus 7. However, in the biblical account of the two magicians who opposed Moses, names are not given. In the Book of Jasher, they are. Therefore, we can note that as Paul wrote the 2nd letter to Timothy, he did so with the knowledge of this ancient text.
Having read this phrase "the book of Jasher" many times, I decided to get the book. I've been reading for a week now, completely mesmerized by the stories, the explanations to questions I've had my whole life, and by the way these verses of ancient text move me.
One section in particular moved me to the point of crying. It comes from Jasher 6, the story of Noah and the Flood. I want to share it with you now because, tomorrow, as I share more of our story ... well, you will understand.
Jasher 6: 28 And the ark floated upon the face of the waters, and it was tossed upon the waters so that all the living creatures within were turned about like pottage in a cauldron.
29 And great anxiety seized all the living creatures that were in the ark, and the ark was like to be broken.
30 And all the living creatures that were in the ark were terrified, and the lions roared, and the oxen lowed, and the wolves howled, and every living creature in the ark spoke and lamented in its own language, so that their voices reached to a great distance, and Noah and his sons cried and wept in their troubles; they were greatly afraid that they had reached the gates of death.
31 And Noah prayed unto the Lord, and cried unto him on account of this, and he said, O Lord help us, for we have no strength to bear this evil that has encompassed us, for the waves of the waters have surrounded us, mischievous torrents have terrified us, the snares of death have come before us; answer us, O Lord, answer us, light up thy countenance toward us and be gracious to us, redeem us and deliver us.
32 And the Lord hearkened to the voice of Noah, and the Lord remembered him.
33 And a wind passed over the earth, and the waters were still and the ark rested.
34 And the fountains of the deep and the windows of heaven were stopped, and the rain from heaven was restrained.
35 And the waters decreased in those days, and the ark rested upon the mountains of Ararat.
36 And Noah then opened the windows of the ark, and Noah still called out to the Lord at that time and he said, O Lord, who didst form the earth and the heavens and all that are therein, bring forth our souls from this confinement, and from the prison wherein thou hast placed us, for I am much wearied with sighing.
37 And the Lord hearkened to the voice of Noah, and said to him, When though shalt have completed a full year thou shalt then go forth (emphasis, mine).