Expositor's Bible Commentary Commentary Luke 11:29

"And when the multitudes were gathering together unto him, he began to say, This generation is an evil generation: it seeketh after a sign; and there shall no sign be given to it but the sign of Jonah." — Luke 11:29 (ASV)

The “sign” Jesus provided to those who wanted one (cf. v.16) is the sign of Jonah himself, whose presence and brief message (cf. v.32), though more minimal compared with the preaching of Jesus, triggered immediate and widespread repentance. The preaching of Jesus carried its own authority, especially when affirmed by the power of God in miracles (e.g., 4:32, 36).