Based on how the Telvanni are presented in Morrowind, these are my speculations on Telvanni gift culture. More than the other Houses and factions, Telvanni famously gives the player the best rewards and the highest pay. On the surface this makes sense, as House Telvanni is supposedly the wealthiest House. But there also seems to be a consistent culture around gifts and giving that I find interesting, and the game hints at a relatively complex Telvanni gift culture with myriad unwritten rules and expectations.
The Silver Staff of Peace is described as being the traditional gift for a Master to give their Mouth, while the Silver Staff of War is the traditional gift to commemorate the ascension to Spellwright. This suggests that there is a layer of a very formalized and prescribed gift culture within House Telvanni, whereupon various occasions and promotions must be recognized by the ranking Telvanni via giving the expected gifts. However, most Telvanni also seem to go above and beyond the bare minimum prescribed by their house, and an unofficial-but-basically-official gift giving culture thrives just underneath this formalized layer. And with good reason.
Despite the cutthroat and decentralized nature of House Telvanni, loyalty within the Masters’ staff/households generally seems to be absolute. Even Mistress Therana’s staff and Mouth are still very loyal to her and continue to run the household for her and eliminate threats to her position (presumably with Felisa Ulessen taking on more and more of the day-to-day decisions). Due to the House’s notorious infighting between the Masters (and their staff by proxy), the Masters reinforce the loyalty of their staff, retainers, allies, etc through the giving of extravagant gifts and endowments. This has gotten to the point that reception of these gifts is an expectation of subordinate Telvanni, and one of their most common perks.
In addition to cementing allies’ loyalty, the Telvanni culture of gift giving also serves to be a way for the Masters to flaunt their wealth and might. They often give gifts of incredible power, items which cannot be recreated in the game, and nonchalantly act as though it were a silly trinket. They obviously know the gift is extravagant and dear, but it is part of the Telvanni game to pretend that it is nothing for them to give so generously (“What, this old thing?”).
Master Aryon even takes it a step further when he gives you Aryon’s Helper, an obviously incredible item which would require orders of magnitude more enchantment capacity than any item has (and therefore must be a very complex and efficient enchantment), and he tells you that it was his first enchantment – hopefully you can find some use for it. I don’t believe for one minute that glove was his first enchantment (because that’s ridiculous), but the purpose of the gifts is two-fold: to keep subordinates and allies happy, while also demonstrating your power and creating/maintaining your reputation as the baddest sorcerer that ever was.
Presumably, then, the other role to be played – that of the recipient – is to play along and be suitably impressed by what a truly remarkable and rare item it is, while the giver continues to insist that it is nothing, a mere bauble. This completes the circle and further reinforces the relationship in both directions. This is important, especially if the recipient is a subordinate, but also for allied peers.