God's promises to Abraham was materialized in the person of Jesus Christ. Abraham obeyed God and received the blessing only for himself but through his seed, all the family of the earth will be blessed...
John called people to repentance but nobody was born again under his ministry, because he himself was not the light and does not know the light neither was he born again. He only knew that someone greater than him is coming but had not seen him before...
When a man understands and believes the gospel, his sins both present, past and future are remitted and credited into Jesus's account and Jesus's righteousness is credited to the man...
The word Repent or Repentance is translated from the Greek word, "METANOIA" which means "to turn around" or a "change of mind". You will agree with me that before the coming of Jesus Christ, men has been in darkness...