Torah Study provides Parnossa

 Sefer Chasidim (309) All those who are constantly learning Torah, G-d sends  His angels to him to bring him all his needs and that is why Torah is described as bread

Rav Yaakov Emden(Migdal Oz): You won’t find a person who is engaged in studying Torah for the sake of Heaven who does not become great and wealthy. If you try refuting this with the verse in Koheles (9:11) that “the wise don’t have bread” – that is only referring to secular scholars. It is not referring to those who are accomplished Torah scholars. And this that we find that there are some of our holy scholars who are poor such as Rabbi Chanina ben Dosa…one should not make the mistake and say that they were unable to find a respectful livelihood – rather the reason that they were poor is because they didn’t want to benefit from their status as Torah scholars … This is quite obvious and certain. There is no question that if Rabbi Chanina ben Dosa and his colleagues wanted they could have been wealthy. They also did not want to interrupt their Torah study even for a moment in order to be involved in work or a trade because of their great love and desire for Torah. Therefore it was with their desire and free choice they bore poverty and lovingly accepted their suffering. However if they wanted to benefit then the option of enjoying wealth was always available and if they wanted to they could have avoided suffering. This of course is true only as long as they studied Torah purely for the sake of Heaven which gives merit to many things which are detailed in the 6th chapter of Avos.

Maharal (Tiferes Yisroel 11:1-2) A person will not acquire success through wisdom, but only through adherence to G-d.  And therefore the question is why man will not gain eternal success by knowing the wisdom that stands on natural means, or the knowledge of the celestial spheres, or the angels that are called  'the separate forms'. Rather success is obtained by learning the Torah laws of damages and the halachic differences between a stove and an oven and other Torah laws. In fact success does not come from worldly knowledge but only by clinging to G-d

Nefesh HaChaim (01:08) ‘You shall gather in your grain...’. What does it come to teach us in light of what is written in Yehoshua 1: ‘This book of the Torah shall not cease from your mouth...’? Could the words be taken literally, to teach: ‘“you shall gather in your grain”—‘behave in them per the ways of the world’—these being Rabbi Yishmael’s words? Rabbi Shimon Bar Yochai said: ‘Is it possible that a person should plow when it’s the season for plowing... what will then become of Torah?’ Rather, when Israel does G-d’s will, their labors are performed by others for them...; and when Israel doesn’t do G-d’s will, they perform their own labor, as it is said “And you shall gather in your grain...”’.” 

Netziv (Shemos 16:23) And all the manna that is left put aside for future use This was to show future generations that G-d helps those who give their lives to give priority to Torah study over earning a living

Rabbeinu Yonah (Avos 03:05): Anyone who accepts the yoke of Torah upon himself, they lift from him the yoke of government: G-d guards from every bad thing the one who makes his Torah study primary and his work flexible, so that he not have to refrain from Torah study. That is because the work of the tzadik receives blessing and he rejoices with whatever he gets. He is therefore not required to do much work for the needs of his livelihood.