From the LCMS website:
Abraham (known early in his life as Abram) was called by God to become the father of a great nation (Genesis 12). At the age of 75 and in obedience to God’s command, he, his wife Sarah, and his nephew Lot moved southwest from the town of Haran to the land of Canaan. There God established a covenant with Abraham (15:18), promising the land of Canaan to his descendants. At the age of 100 Abraham and Sarah were finally blessed with Isaac, the son long promised to them by God. Abraham demonstrated supreme obedience when God commanded him to offer Isaac as a burnt offering. God spared the young man’s life only at the last moment and provided a ram as a substitute offering (22:1–19). Abraham died at the age of 175 and was buried in the Cave of Machpelah, which he had purchased earlier as a burial site for Sarah. He is especially honored as the first of the three great Old Testament Patriarchs—and for his “righteousness before God through faith” (Romans 4:1–12).