Matt matures and grows more courageous over the course of Gathering Blue. In chapter 1, Matt meets Kira coming back to the village from the Field of Leaving. She hopes he will help her rebuild her cott, but he declines, saying his mother will whip him if he doesn't finish gathering firewood. However, his additional reason is that the women, led by Vandara, have claimed Kira's space. Matt warns her, but in a whisper, showing he fears not only a whipping from his mother but also repercussions from the scar-faced Vandara.
Matt becomes more daring later in the book. He plants himself in the middle of the group of men who are preparing for the hunt, although he is too young to go. He wants to do something adventurous to prove his "manhood." He allows Thomas and Kira to dissuade him from that venture, but he later disappears. Kira and Thomas learn he received a harsh beating from his mother for stealing food for his journey, but he endured it so that he could go "yonder" to obtain the blue dye for Kira as a special "giftie." He told his mother he would never return to their home in the Fen, and he keeps that vow. He makes his way to the other village and brings Kira's father back to her, as well as the plants for making blue dye. He becomes the "tie" who will go back and forth between the two villages, allowing Kira and her father to keep in touch.
Matt changes from a wild little boy who steals and plays with other boys and his dog to a brave youngster who makes a journey that no one else in the village has attempted. He faces personal pain and danger not for his own gratification, but to help a friend. This shows how he has matured over the course of the novel.