Theudas was a leader of an unsuccessful movement mentioned by Gamaliel in Acts 5. Gamaliel recalled that Theudas claimed to be somebody and attracted about four hundred followers, but after he was killed his followers dispersed.
Biography
Gamaliel cited Theudas while counseling the Jerusalem council about how to respond to the apostles. According to his speech, Theudas arose claiming importance, about four hundred men joined him, and after he was killed the movement came to nothing. Gamaliel then mentioned Judas the Galilean as another example before arguing that a merely human movement would fail on its own. The Jewish historian Josephus describes a later figure named Theudas during the governorship of Cuspius Fadus, creating a well-known chronological question if the two are assumed to be identical. Acts itself gives too little information to establish that they must be the same individual.
Biblical Significance
Theudas functions in Acts as a historical comparison used in Gamaliel's argument. His failed movement serves as a foil for the Christian mission: the council is warned that if the apostles' work is from God, human authorities will not be able to overthrow it.