Today, I will discuss some of the festivals and holy times sacred to Hephaistos.
The first festival I will discuss is the Khalkeia. This is an Athenian festival that took place on the last day of the month Pyanepsion, around October/November. It honours Hephaistos as Khalkeus, the God of Bronze-Smithing. As such he is worshipped particularly by bronze-smiths, but other craftsmen also worship him. The festival may have originally been partaken in by all Athenians, but it seems, based on what I read on theoi.com, that over time only craftsmen still celebrated it.
I also found mention of a Hephaistia festival, mentioned in the Suda, a Byzantine lexicon, but I don’t know much about it other than that it featured torch-races. This tradition was something that the Suda reports the Athenians first did when sacrificing to Hephaistos, and then spread to the Panathenaia and Prometheia festivals as well.
That’s really all I found for specific ancient celebrations. Obviously, there must have been several festivals dedicated to him in his main cult centres of Lemnos and Sicily, but nothing specific that I could find.
As for anything modern, it seems to me that the first day of this month, Labour Day, would be an excellent opportunity to worship Hephaistos as a God of Craftsmen and Labourers. Any other celebrations in whatever country you live in to commemorate labour and industry can be seen as occasions to worship Hephaistos.
As a Lame God, I believe he would also be a patron Deity for people with disabilities. Perhaps particularly physical disabilities, perhaps also including mental disabilities. Divination would have to be done, but perhaps Athena would be more connected with mental health and disabilities in her form of Athena Hygieia. Again, more divination is needed.
However, as a God of people with disabilities, any national, international, or local days to call attention to these things would be an opportunity to worship Hephaistos. This month is, I believe “National Month of Mental Health” in the USA, which would be an example of such things. During my research, I discovered this page with “Awareness Days/Months/Years“, which might serve as a guideline to find such days.
And that’s about it for today.