When Jesus was tempted by Satan in the wilderness he combated him with reference to the Scriptures. He repeatedly said, “It is written,” before quoting a passage and fending off the temptation (Matt. 4:4, 6, 7, 10). In truth, Jesus is continuing a long tradition of referring to the Scriptures as authoritative (Jos. 8:31; 2 Sam. 1:18; 1 Kgs. 2:3; 2 Kgs. 23:21; 2 Chr. 23:18; 31:3; 35:12; Ezra 3:2, 4; 6:18; Neh. 8:15; 10:34, 36; Ps. 40:7; Isa. 65:6; Dan. 9:13), a trend we find continued in the apostles’ preaching in Acts and Paul’s letters. Get some Bible software (BibleWorks and Logos are best but e-Sword is great too, and it’s free) and run a search on the term and check out its uses.
Earlier in Matthew’s Gospel, upon learning of the birth of Jesus the King of the Jews, the troubled Herod gathered the chief priests and scribes and asked where Jesus was to be born. They confidently answered Herod and said “in Bethlehem of Judea,” which they supported by saying, “for so it is written by the prophet.” Later in Matthew’s Gospel Jesus co-signs John the Baptist’s ministry by saying that John was the one of whom “it is written,” referring to Malachi’s prophecy about the one who would prepare the way for God (Matt. 11:10 cf. Mal. 3:1).
Even later still, when Jesus overturns the tables in the temple and chases away those who bought and sold he justifies his righteous indignation by saying, “it is written” (Matt. 21:13 cf. Isa. 56:7; Jer. 7:11). He can say, “For it is written, ‘I will strike the shepherd, and the sheep of the flock will be scattered’” and guarantee that his disciples would fall away from him because of his confidence in Scripture’s authority (Matt. 26:31 cf. Zech. 13:7). And of course he should have such confidence, the LORD’s will will not return to him empty and it will accomplish the purpose and succeed in the thing for which he sent it (Isa. 55:10-11).