Baptism of the Holy Spirit 18:38
You see reformation day isn’t about cards or presents or activities (and hopefully never will be!), but rather it’s simply a reminder in the year of one of the greatest events in the history of Europe, the Protestant Reformation, and what it stood for (helpfully summed up in 5 Solas). It’s an annual reminder of the power of God’s Word and of the glory of the gospel that we are saved by grace alone, through faith alone, in Christ alone, to the glory of God alone.
For some reason though, Reformation Day doesn't seem to be all that big a deal in Pentecostal and charismatic circles. Now, I’m sure that part of that is that we just tend not to be very historically rooted; we tend to forget about most of what happened in the life of the church either before the Welsh Revival or before the charismatic renewal. (In fact, sometimes it feels like we easily forget anything that happened in the life of the church before last Sunday!) And this aversion to history is definitely something we need to get over quickly (after all we profess that we believe in “the communion of the saints”, not just the communion of the saints who happen to be on earth at this particular moment).