The seal shows per pale three lions rampant
Little is known about Matthew, and research is complicated by the use of Fitz, son of, in the name of a person at the time. His father, John, had a father named Matthew, and was known as John FitzMatthew. In his turn his father was Herbert, and known as herbert FitzHerbert.
Because of this it is usually very difficult to trace a family.
Matthew does not appears in any of the published rolls, but there are
Herbert FitzMatthew, in Glover's Roll, B78, who bears
Per pale azure and gules three lions rampant or
Philip FitzMatthew, in St George's Roll, E306, who bears
Per pale gules and azure three lions rampant ermine
Reynaud FitzPiers, in Glover's Roll B77, The Camden Roll D135 & St George's Roll, E47, bears
Gules three lions rampant or