Gemara:


Ein Ayah: A levush (the same root of titlabesh) refers to an undergarment and a k’sut (the same root as titkaseh) refers to an outer garment.
Realize that when Bnei Yisrael are in exile, Hashem’s power is not recognizable, as other nations enslave His children, prompting people to declare: "Where are His acts of might?" (Heaven forbid) (based on Yoma 69b). However, at those times, Hashem’s mercy is very recognizable, as "a single lamb survives among seventy wolves" (based on Tanchuma, Toldot 5), and without His daily mercy they would stand up against us to destroy us.
However, at the time of Israel’s greatness, His mercy will be in hiding. While He Who protects Israel will protect us from all sorts of bad things that could arise, it will not be felt at the time of greatness. As the dangers will not be so visible, so will the need for mercy go unnoticed. In that way, mercy will be rightly described as an undergarment, which is not noticeable. To the contrary, the power will be noticeable, as Israel’s greatness will be famous throughout the world. We will then correctly pray that Hashem should dress Himself with mercy, internally, for both the individual and the collective will always need His mercy. However, we ask for a time where His power will become famous, as the nations of the world will know that there is a G-d over Israel and "all of the nations of the world will know that the Name of Hashem is called upon you [Israel]" (Devarim 28:10).

The Light of Torah as a Replacement for Physical Pleasures
(based on Ein Ayah, Berachot 2:31)

Gemara:


Ein Ayah: A person’s heart naturally yearns to deal with matters of this world, in a life of social affairs. In these matters, he is full of interest, and his eyes are satiated only with pleasures of the senses according to the specifics of each. When one elevates himself by separating himself from indulgence in these pleasures, he is on the right path if he is able to do so in a manner that he will not acquire a "darkening of his spirit" due to abstention from physical pleasures. Rather his spirit will be full of light and happiness. This is possible if he will be wise enough to enthusiastically see the great value of the exchange in lifestyle, so that the light of Torah will fill the void left when he distanced himself from a life of senses and related activities. Only in that way will he acquire true completeness.
This is what Rabbi Chiya meant by the Torah being the person’s craft. Such a person could be on the highest level of limiting physical pleasures, but because of the involvement in Torah, he will not need to be involved in the activities of the world and the senses. He asked that his heart should not be saddened by the lack of natural interaction among those who are occupied with the physical world and that his eyes should not be darkened by a yearning to enjoy sensual pleasures. Rather his limitation of pleasures should be done with love and an uplifting of the spirit.