‘Then certain of the scribes and Pharisees answered him, saying, “Teacher, we would see a sign from you.”
‘Then' is a connecting word (compare Matthew 12:22) and, like most connecting words in the Gospels, must not be overpressed. It indicates a loose connection to give some indication of continuity, without being specific.
‘Certain of the Scribes and Pharisees' may indicate an official deputation, or may simply indicate that not all Scribes and Pharisees were to be seen as involved. Not all Scribes and Pharisees behaved wrongly towards Jesus.
“Teacher, we would see a sign from you.” They came seeking a sign, something typical of Jewish thinking (compare Matthew 16:1-4; 1 Corinthians 1:22). Their Scriptures had taught them to expect the spectacular. Later Rabbinic writings would speak of Rabbis proving themselves on request by turning water into blood, or moving trees some distance, or making a river move backwards. Compare Moses (Exodus 4:9) and Hezekiah (Isaiah 38:8). They were, of course, legends, but they demonstrated the kind of things that the Rabbis saw as a sign. They would have loved the one suggested by Satan (not a good source for suggestions) that He throw Himself off the roof of the Temple. But of what would they have been convinced? It would not have changed their attitudes towards Jesus' teaching. It would not have changed their hearts. The children of Israel who saw all the signs of Moses still had to perish in the wilderness because of unbelief and disobedience.
‘Teacher.' A regular address to Jesus by Scribes, Pharisees, and others seeking to be polite. In each case they were those who would see themselves as at least on a level with Him in status (Matthew 8:19; Matthew 9:11; Matthew 17:24; Matthew 19:16; Matthew 22:16; Matthew 24:36). And it was even used by Jesus speaking of Himself (Matthew 26:18). It therefore here ranks Jesus alongside other teachers, including Solomon in his capacity as a wisdom teacher.