My wife asked me the following question, which I don't really know the answer to: there is a group of women who get together regularly to daven shacharis together and say tehillim. Does the place that they daven have the din of a beis knesses?
My wife had a hava amina that since there was no minyan, it could not be a beis knesses, but I don't know if the two ideas go hand in hand. You can have a minyan held even semi-regularly in a place that does not have the status of a beis knesses (in some communities where people live far from shul there are something Friday night minyanim in people's homes), so why can't you have a place that has the status of beis knesses but has no minyan? It's just the other side of the same coin.
Turning to the parsha, the sefer Nesivei Chaim raises the following question: The Rambam in peirush hamishnayos writes that if a navi says something good is going to happen, you can take it to the bank -- Hashem will never go back on that promise. (The Meshech Chochma quotes this in a number of places which I posted about already here and here.) In the beginning of our parsha, Hashem tells Moshe to tell Bnei Yisrael that he will bring them to Eretz Yisrael, "V'hai'veisi eschem el ha'aretz..." (6:8) Based on the Rambam, that promise should be irrevocable, guaranteed 100%. Yet, that promise was in fact never fulfilled. The generation that left Egypt (at least those over 20) all died in the desert and never made it to Eretz Yisrael. Doesn't that contradict the principle the Rambam sets out? (See Ohr haChaim, Ibn Ezra, Seforno)
Rav Elezri answers by quoting the Rambam's reasoning for his principle. How can you tell a true prophet from a false one? Simple: a true prophet can make claims that are 100% guaranteed. The Rambam's principle serves as a check against doubt and as a means of testing the veracity of nevuah.
Such a test and check may be necessary for all other nevi'im, says Rav Elezri, but not so for Moshe. "V'gam becha ya'aminu l'olam," the Torah promises. Belief in the prophecy of Moshe is a cardinal tenant of our faith. Therefore, since no check against doubt is needed, there is no guarantee of every promise spoken by Moshe coming true.
I think you can make the same argument with a slight twist. In our parsha, Moshe complains to Hashem that if Bnei Yisrael did not listen to him, surely Pharoah will not listen either, "v'ani aral sefasayim," not to mention that he also has a lisp. Why does Moshe bring up his lisp here? Didn't he already make the argument in last week's parsha, and Hashem had already responded that he gives the power of speech and will help Moshe. Why are we revisiting the same argument all over again?
The Techeiles Mordechai, R' Schwadron, explains that Moshe was unique in that "Shechina m'daberes b'toch grono," it was as if G-d was speaking from his mouth. Moshe thought this was the help Hashem would give to overcome Moshe's lisp. However, there is a downside to this type of help. The Rambam's principle only works for a promise made by a navi, not a promise made by Hashem himself.
Moshe thought that if Bnei Yisrael could ignore him, it must be because he is guilty of some cheit, and that cheit is interfering with the message. If so, perhaps Pharoah would not listen. Perhaps the geulah itself would be in jeopardy. "Ani aral sefasayim" -- the words aren't my words, thought Moshe -- they are G-d's words. Therefore, the Rambam's principle that guarantees the words of a navi will come true doesn't apply, and who knows what will happen?
So maybe this is also why the Rambam's principle does not apply to the promise of "V'hei'veisi..." When Moshe made that promise, it was not words of a navi that Bnei Yisrael heard, but rather it was "Shechina m'daberes m'toch grono."