Genesis 17:1 - 14
NKJV - 1 When Abram was ninety-nine years old, the LORD appeared to Abram and said to him, "I am Almighty God; walk before Me and be blameless. 2 "And I will make My covenant between Me and you, and will multiply you exceedingly."
For follow-up discussion and general commentary on the topic. Comments are sorted chronologically.