Tell me why Christ waited to come when he did? Why not during the time of Moses, or Abraham? Why let all these generations live without his word?
The Old Covenant is with God. Jesus is God.
John 8
52: (So) the Jews said to him, “Now we are sure that you are possessed. Abraham died, as did the prophets, yet you say, ‘Whoever keeps my word will never taste death.’
53
Are you greater than our father Abraham, who died? Or the prophets, who died? Who do you make yourself out to be?”
54
Jesus answered, “If I glorify myself, my glory is worth nothing; but it is my Father who glorifies me, of whom you say, ‘He is our God.’
55
You do not know him, but I know him. And if I should say that I do not know him, I would be like you a liar. But I do know him and I keep his word.
56
Abraham your father rejoiced to see my day; he saw it and was glad.
57
So the Jews said to him, “You are not yet fifty years old and you have seen Abraham?”
58
Jesus said to them,i “Amen, amen, I say to you, before Abraham came to be, I AM.”
59
So they picked up stones to throw at him; but Jesus hid and went out of the temple area.
There are no generations that have lived without God’s Covenant, and His Covenant His Word. Jesus is the New Covenant, to which we belong by virtue of our baptism.