Most likely, this term refers to Jesus’ contemporaries, the people who lived on earth when he came to earth.1 These people refuse to believe and accept him as the Messiah. It could also be that Jesus is drawing a parallel between the Pharisees and the wilderness generation. The wilderness generation was a group of Israelites who constantly put God to the test and badgered Moses for signs that God was with them (Exodus 17:7; Numbers 14:11; Deuteronomy 6:16; Deuteronomy 29:2–6; Psalm 78:11–32; Psalm 95:8–10). The Pharisees are behaving in a similar unbelieving manner.2
12 And he sighed deeply in his spirit and said, “Why does this generation seek a sign? Truly, I say to you, no sign will be given to this generation.”