It's Pentecost!
When the time for Pentecost was fulfilled, they were all in one place together. And suddenly there came from the sky a noise like a strong driving wind, and it filled the entire house in which they were. Then there appeared to them tongues as of fire, which parted and came to rest on each one of them. And they were all filled with the Holy Spirit and began to speak in different tongues, as the Spirit enabled them to proclaim. // Acts 2