Here’s what a couple of scholars say regarding Early Church belief in transubstantiation.
J.G. Davies explains how the Hebrew mind would have assimilated Eucharistic statements:
“The Hebrew, unlike the Greek, was not interested in things in themselves but only in things as they are called to be. He was not concerned with an object as such but with what it becomes in relation to its final reference according to the divine purpose. The meaning of an object therefore does not lie in its analytical and empirical reality but in the will that is expressed by it. Hence Jesus could say of a piece of bread: ‘This is my body.’ The bread does not cease to be bread, but it becomes what it is not, namely the instrument and organ of his presence, because through his sovereign word he has given it a new dimension.” (Davies, J.G., The Early Christian Church, (New York: Anchor Books, 1965,) p. 54.)
Edwin Hatch asserts that “it is among the Gnostics that there appears for the first time an attempt to realize the change of the elements to the material body and blood of Christ.” (Hatch, The Influence of Greek Ideas and Usages Upon the Christian Church, p. 308.)
I hope this helps…