The Gemara (Berachos 26b) cites two different sources for our daily tefillos. According to Rebbe Yosi b'rebbe Chanina, our tefillos were instituted by the avos. Rebbe Yehoshua ben Levi however maintains that our tefillos correspond to the daily korbanos.
The Gemara subsequently (27b) disputes the nature of tefillas arvis. Rabban Gamliel maintains that tefillas arvis chova, that the maariv tefilla is compulsory, whereas Rebbe Yehoshua argues that tefillas arvis reshus, that maariv is elective.
Although the Gemara never connects these two themes, Rashi (Shabbos 9b) explains that the source and extent of our obligation to daven maariv are clearly linked. If tefilla is rooted in the practice of the avos, there is no difference between shacharis, mincha, and maariv. According to Rebbe Yehoshua ben Levi, however, who bases tefilla on korbanos, one can easily distinguish between shacharis and mincha, which are patterned after fixed korbanos, and maariv, which does not correspond to a particular korban, but rather to the remaining parts of the korban which would burn through the night.
The Netziv, however, observes (Sheilta 8) that this cannot be the view of Rebbe Achai Gaon. Although the Sheiltos maintains tefillas arvis reshus (maariv is elective) he nevertheless cites the source of Rebbe Yosi b'rebbe Chanina basing tefilla on the avos. Why however, should the tefilla of Yaakov avinu be any different than the tefillos of Avraham and Yitzchok?
The Netziv explains that an answer can be found in the very phrase vayifga bamakom, he encountered the place, which describes the tefilla of Yaakov avinu. The Gemara (Chulin 91b) comments "ki mata l'Charan amar, efshar avarti al makom shehispalelu avosai va'ani lo hispalalti?" - "when Yaakov reached Charan he exclaimed, how could I have passed the place where my fathers davened and not have davened there myself?"
Unlike the tefillos of Avraham and Yitzchok, when the Torah simply states that they davened, here the passuk attributes the tefilla of Yaakov avinu to a particular time and place. Apparently, the tefilla of Yaakov was not a categorical obligation, but rather a response to his unique circumstance. If so, the Netziv observes, the view of Rebbe Yehoshua who holds tefillas arvis reshus can be understood based on the tefilla of Yaakov avinu.
Tefillas arvis, which was instituted by Yaakov avinu, emphasizes the appropriateness of tefilla when one is surrounded by darkness. The Meshech Chochmo explains (Braishis 46:2) that twice, Hakadosh Baruch Hu appeared to Yaakov avinu at night, b'maros layla. Although Yaakov avinu was forced to leave Eretz Yisroel and endure the difficulties of galus, Hakadosh Baruch Hu reassures him, specifically at night, that even b'cheshkas hagalus one can experience hashroas hashechina.
May we, the descendants of Yaakov avinu, embrace the priorities of our avos, enabling the light of Torah and tefilla to permeate the darkness of galus.