We have often referred to the gemara in B'rachot's fourth perek, that teaches us a "dispute" as to whether our prayers we fixed to correspond to the daily sacrifices in the Beit HaMikdash, or it was our Avot that fixed them.

Notice that the word 'dispute' is in quotation marks, because there really is no dispute - both opinions are correct because our Avot and the Beit HaMikdash combine to produce the davening as we know it today.

Let's go back a step. When the gemara quotes the pasuk from Vayeira that Avraham got up early in the morning and returned to the place where he had stood (before G-d), it does not mean that Avraham Avinu davened Shacharit, as we know it.

So too, when the pasuk at the end of this week's sedra tells us that Yitzchak went out in the field before evening to commune with G-d, it is not telling us that Yitzchak Avina davened Mincha, as we know it.

So too for Yaakov Avinu and Maariv in Parshat Vayeitzei.

What the gemara is teaching us is that our Avot inspired us to pray to G-d morning, (after)noon, and night. Or that they inspired our Sages to shape our davening and require us to daven three times a day.

We are not discussing now the formalization of the texts that became our daily davening.

Pardon the jump. The point (one of the points) is that davening is independent of korbanot and the Beit HaMikdash. There is ample evidence of that in the Torah.

However, during the time of the Beit HaMikdash, our Sages decided that we should sync of davening and the Avoda in the Mikdash. We should daven in the morning at the same time (roughly) that the morning sacrifice was offered. This goes a long way towards linking each of us with all of Klal Yisrael.

And after the Beit HaMikdash was destroyed, our davening was further formalized to allow our davening to temporarily replace the korbanot. This should be seen as an extra task of our davening, not their essential character.

Note the following, even though the topic is for from being covered well - End of Chayei Sara, Yitzchak 'davens' Mincha. Beginning of next sedra, he and Rivka pray for a child. Different aspects of prayer. Both important.