John 2:18 New English Translation

¹⁸So then the Jewish leaders^[a] responded,^[b] “What sign can you show us, since you are doing these things?”^[c]

John 2:18 tn Or “the Jewish authorities”; Grk “the Jews.” In NT usage the term ᾿Ιουδαῖοι (Ioudaioi) may refer to the entire Jewish people, the residents of Jerusalem and surrounding territory, the authorities in Jerusalem, or merely those who were hostile to Jesus. Here the author refers to the authorities or leaders in Jerusalem. (For further information see R. G. Bratcher, “‘The Jews’ in the Gospel of John,” BT 26 [1975]: 401-9.)
John 2:18 tn Grk “answered and said to him.”
John 2:18 sn The request “What sign can you show us” by Jesus’ adversaries was a request for a defense of his actions—a mark of divine authentication. Whether this was a request for a miracle is not entirely clear. Jesus never obliged such a request. Yet, ironically, the only sign the Jewish leadership will get is that predicted by Jesus in 2:19—his crucifixion and resurrection. Cf. the “sign of Jonah” in the synoptics (Matt 12:39, 40; Luke 11:29-32).

New English Translation (NET)