After the resurrection and ascension of the Lord Jesus Christ, his disciples (120 of them) were gathered in one accord in the upper room. Then suddenly, there came a sound from heaven as of a rushing Mighty wind, and it filled the entire house where they were sitting. Gloven tongues, like as of fire sat on each of them, and they were all filled with the Holy Spirit. (Acts 2:1-4).
When they were all filled with Spirit of God, they began to speak words of praise and the Almighty God in other tongues. Because of the way they were acting and talking some of the people look at them mocking them, thinking they were drunk.