apostalic vs other source in orthodoxy

[Ran the Man]

This is something I want to study deeper, the possible other sources of tradition in orthodoxy besides the apostle. Author Christos Ware has mentioned this, that tradition in the Orthodox Church has come down from two sources.
Also is it possible that hesichasm is from the Buddhists? There are too many similarities between it and Zen, not that i practice either, but i have studied Zen of course, living in Asia.