(1) what are the does it mean tefilas arvis reshus and what are the practical implications of it?
(2) Also how does the one who says the tifelos are corresponding to the avos explain arvis reshus?
M. O., newyork,ny
This is not meant to be a Halachic ruling, but rather a discussion of the subject.
1. It means that Ma'ariv is not an obligation like other Tefilos, but rather it is appropriate to Daven at that time. However, being that men have accepted upon themselves to always Daven Ma'ariv, one must always Daven Ma'ariv (see Mishnah Berurah 106:4). There still are some halachic leniencies that result due to this concept. For example, the Shulchan Aruch rules (O.C. 268:13) that if someone did not Daven Ma'ariv on Shabbos night and he hears the entire Chazaras ha'Shatz (without interruption) from beginning to end, he fulfills his obligation of Davening the Shemoneh Esrei of Ma'ariv. The commentaries (Magen Avraham ibid. and others) explain that this leniency is only due to the concept of Tefilas Arvis Reshus.
2. The Pardes Yosef gives a nice explanation in the beginning of Parshas Yayeitzei. He says that Yaakov Avinu in fact wanted to Daven Minchah, not Ma'ariv. However, Hash-m made the sun go down quickly, causing him to Daven a new Tefilah called Ma'ariv. Accordingly, even Yaakov Avinu did not truly establish that one should Daven at this time. This is why Tefilas Arvis Reshus.
For any practical Halachic ruling, consult a Rav.
All the best,
Yaakov Montrose