For Catholics and other western Christians, May 19 is Pentecost Sunday, recalling the day when the 12 Apostles received the Holy Spirit as "tongues of fire" that came to rest on each of them. Whether their fear and hesitation miraculously vanished in that instant, or whether the process was more gradual than that, the Apostles became fearless preachers, all (except, according to tradition, John) dying for their faith in Jesus.
May 19 is also May-Ray Day, celebrating the return of sunshine (the rays, you see) and encouraging people to get out and enjoy the nice weather. If it is nice. And, if it is nice on Sunday, you may wish to observe Plant Something Day, assuming that you live in a region where still one more frost is unlikely.
The Who's Pete Townshend turns 68 on Sunday (born May 19, 1945). According to Usual Suspect History.com, Townshend wrote "My Generation" on his 20th birthday, May 19, 1965. The linked article provides an explanation of the line in that song, "Hope I die before I get old."