Abraham (אַבְרָהָם in Hebrew, originally called Abram,הָעִבְרִי) is the first Patriarch, the founder of Judaism in its roughest form, and the original descendant of the Israelites, the Hebrew people, Samaritans & Jews, and the founder of Israel.
Terah had three children, Abram being the oldest. Abram later married Sarai, his sister, and they went with Lot, his nephew (Lot's father was deceased) and Terah to go to Canaan, but ended up going to Terah instead. It was there that Abram met with God, who appeared before him. God told him to go to Canaan, that He would aid him in his journey. Terah died.
Sarai, Abram, and Lot travelled to Canaan, and lodged there for awhile, until a famine was cast upon the land. So they travelled to Egypt until it passed. Abram was afraid that the Egyptians would fall in love with his wife and kill him to get her, so he told Sarai to pretend to be his sister, which she agreed to. In Egypt, the princes of the Pharoah saw her beauty and saw that she was "unmarried" as far as they knew, so they were brought to the Pharoah, who fancied her and gave them provisions to woo her. But God cursed the Pharoah because of his sins, prompting Abram to confess that they were not just related by blood, but also by marriage. The Pharoah was furious and sent them out of Egypt.
When they returned to Canaan, Lot and Abram shared a pasture. This presented a problem because of their huge livestocks when they were being counted. So Abram suggested they split up, and offered Lot the north or south area, but Lot instead went east where it was well watered, and settled in Sodom. Abram went south and built an altar to God.
There was a great battle a little bit later, and Lot was taken prisoner. A servant escaped and told Abram of this, to which Abram responded by sending 318 well-trained servants to fight back. They defeated the Elamite army, freeing Lot and his family, who returned to Sodom after that. After returning home, Abram was blessed by a priest and king. Abram responded by giving a tenth of everything to him. The king of Sodom offered things to Abram for his assitence, but he refused any gifts.
One day, Abram was given a vision by God, Who told him of the future bondage of Israel, and promised to give him much land, establishing the first Abrahamic covenant. This covenant would continue to be added upon throughout Abram's life.
Abram and Sarai wanted children, but Sarai was barren, so the solution they thought up would be for Sarai's maidservant, Hagar, to birth a son and heir. After she became pregnant, Hagar began to feel more entitled than Sarai, feeling as or more important than her. So, Sarai began to mistreat Hagar, and she fled. But then an angel of the Lord appeared to her, and told her to return, and name her son Ishmael. She did so.
Thirteen years later, God gave Abram a new name, Abraham, and gave him instructions for the circumcision of his offspring. He quickly circumcised himself and Ishmael. God then gave Sarai a new name, Sarah, and said He would give them a son. Abraham laughed and didn't believe at first.
A little while later, Abraham saw three men coming near him, and he knew that they were God in three persons. He went to them and bowed and worshiped them, and then went to Sarah's tent to get some cakes for them and told a servant boy to get some meat. They then ate. They told him that Abraham and Sarah would have a child, and Sarah laughed, to which They replied by asking if anything was too hard for God. So Sarah stopped her laughing.
After eating, Abraham and his guests discussed the destruction of the wiked cities of Sodom and Gomorrah. Abraham argued it down to if ten righteous men were found there, it would not be destroyed, so two of the three guests went into the city to go and see the righteous people. They only found Lot and his wife, so they told him to leave and they would destroy the city.
Later on Abraham and Sarah went to Philistine, where King Abimelech lived. Abraham again said Sarah was his sister and not his wife, and the king sought after her. God appeared to him in a dream and said He would kill him if he touched the married woman, to which the king reacted by asking Abraham why he brought such grief to the kingdom. Abraham replied by saying she was his sister, but also his wife, and wasn't lying at all. The king gave Sarah back as well as gave him many gifts. There was a bit of violence between Abraham and Abimelech's servants, to which they responded by forming a pact on a well in Beersheba, and named it that.
Birth of Isaac
The next year, Sarah birthed a son to 100-year-old Abraham, and named him Isaac. After Isaac was weaned, he was thrown a celebrative feast, of which Ishmael mocked.
Sarah saw Ishmael's mocking of Isaac, so she sent him and Hagar away, taking away any kind of inheritence from them. Abraham saw this and thought it wasn't right, so he asked God what to do, Who told him to follow what his wife told him to, for it was His will. Abraham gave them food and water, and sent them off into the wilderness, where they met with an angel of the Lord, who told them it would be okay. They found Ishmael a wife after that.
God told Abraham to sacrifice Isaac, so he sorrowfully did so. He brought Isaac to a mountain, put him on the altar, and almost swung the axe onto him, but was stopped by an angel of the Lord, who told him it was just a test, and then they sacrificed a ram stuck in the thickets instead.
After Sarah died, Abraham placed her body in the Cave of the Patriarchs, and took a concubine as a wife to bear him more children. He later died, was taken to the same cave, and was buried there near his wife.
Abram means "father of multitudes" or "high father". Abraham means "our father" or "father of many."