The Traditions Of Matthias

Synopsis
The Traditions Of Matthias, sometimes called the Gospel Of Matthias, is a lost work frequently quoted from by Clement of Alexandria. According to him, Matthias, the replacement Apostle to Judas Iscariot, was the same as the Zaccheus, the rich tax-collector who climbed a tree to witness Christ preach.

Canonicity
While it was never canon, at least Clement saw the work as legitimate.

Clement of Alexandria, Stromata 2.9.45.4
But the begining of this is to marvel at things, as Plato says in the Theatetus and as Matthias says in the Traditions when he urges, "Marvel at what is present," laying this down as the first step toward the knowledge of things beyond.

Clement of Alexandria, Stromata 3.4.26.3
They say that Matthias also taught this: "To fight with the flesh and misuse it, without yielding to it through undisciplined pleasure, so to increase the soul through faith and knowledge."

Clement of Alexandria, Stromata 4.6.35.2
So Zaccheus whom they call Matthias, the chief tax collector, when he had heard that the Lord had esteemed him highly enough to be with him, said, "Behold, half of my present possessions I give as alms, and Lord, if I ever extorted money from anyone in any way, I return it fourfold."

At this the savior said, "When the son of man came today, he found that which was lost."

Clement of Alexandria, Stromata 7.13.82.1
They say that Matthias the apostle in the Traditions says at every opportunity, "If the neighbor of an elect person sins, the elect person sins. For if he had led himself as the word dictates, the neighbor would have been in awe of his life so that he did not sin."