Gemara: Rav Chisda was holding two portions of cow meat (given to kohanim). He said: "I will give these portions to whoever comes and tells me a new teaching of Rav." Rava bar Machsiya said in the name of Rav: "One who gives a present to his friend should inform him, as it says: ‘…to know that I am Hashem who sanctifies you’" (Shemot 31:13). Rav Chisda gave him. [Rava commented about Rav Chisda’s great love for Rav’s teaching:] "That is as Rav said: ‘Nice clothing is dear to those who wear them.’" Rav Chisda said: "The second teaching is even better than the first. If I had more, I would give you."

Ein Ayah: Eating meat is somewhat distant from the way of the Torah, and it is a concession to the yetzer hara when people have a craving for it (see Devarim 12:20). More fundamentally, man needs meat to strengthen himself, which is crucial for his physical and spiritual success. Were it only for physical success, eating meat would still be immoral in relation to the animal kingdom, but since spiritual advancement will lead to an eventual progression toward world spirituality that will encompass animals, it is fair to partake of animal meat until that historic stage is reached. It is therefore most appropriate for meat to be eaten in the context of an increase in wisdom, and it is problematic for an utterly non-spiritual person to eat meat (see Pesachim 49b). That is why the Torah instructed to give specifically meat to kohanim (the only other species that the Torah, not the Rabbis, required to be given to kohanim are grain, wine, and olive oil), as cow meat is particularly capable of spawning deep thought (Bava Kama 72a).
There are two special elements to acquiring the Torah taught by a scholar of historic proportions: the wisdom itself, and the clearer picture it gives of the holy Torah personality, which is collected from the sparks emanating from his various teachings. That is why one who helps complete a disciple’s picture of his master by providing a missing piece of knowledge deserves to receive a double portion [as Rav Chisda gave].
The first teaching Rava told captures the idea that it is better to sacrifice the personal high level of doing acts of kindness without external gain in order to allow the world to be improved by allowing the recipient to experience gratitude, an attribute that can affect the masses. This spiritual sacrifice is reminiscent of the great person’s eating of meat so that he can have strength even though he feels guilty for causing an animal’s death, as we expect a great person to feel (see Bava Metzia 85a).
The excitement Rav Chisda felt for the teachings of his great master, Rav, showed that he was fit for the thoughts of Rav and that they allowed him to grow from and implement them practically. This is not to be taken for granted, as there are different paths of wisdom to which different scholars gravitate, and one should follow his feeling. That is why Rava related another teaching of Rav by equating Rav Chisda’s connection to that of one who is used to wearing a certain fine garment, which is a level beyond just owning the clothing.
Rav Chisda was even more taken by Rava’s second teaching in Rav’s name because it related not only to an intellectual teaching but to a practical one, which is the highest utilization of his master’s teachings. It would have been most appropriate to capture the specialness of learning this new teaching by performing an action – giving a present to Rava – which Rav Chisda lamented he was unable to do at that time. However, the feeling of wanting to do so stemmed from a feeling of natural sanctity and an internal inclination.