8:11 The antagonism of the Pharisees was persistent (2:16-18, 24; 3:6; 7:1-5; 10:2; 12:13, 15). The request for a sign is at times acceptable (Judg 6:36-40; 2 Kgs 20:8-11; Isa 7:10-12; see also John 2:18-19), but in this case it was obstinate testing of God. • The sought-after sign was not a healing, an exorcism, a raising from the dead, or a nature miracle, for there had been many of these already, and Jesus’ ability to work such signs was well known (Mark 1:32-34, 45; 3:7-12; 6:53-56) even to the Pharisees (3:22). What they sought was a miraculous sign from heaven—that is, directly from God—that would demonstrate once for all that Jesus was the Christ. No sign, however, could ever convince them of this. For those whose hearts were open to the truth, the miracles that Jesus had already done (Luke 7:22) were clear and irrefutable signs that Jesus was the Messiah, the Son of God. For those outside (Mark 4:11-12), no sign could make them believe (cp. Luke 6:19-31).

8:12 I tell you the truth: Jesus’ response was as strong as an oath meaning, “[May God’s judgment fall upon me] if I give this generation any such sign.” Such oaths express an unbending commitment (see Gen 14:22-23; Num 32:10-11; Ruth 1:17; 1 Sam 3:17; 20:13; 2 Sam 3:35; 19:13). • Jesus elsewhere describes this generation as “adulterous and sinful” (Mark 8:38) and “faithless” (9:19).