Eliezer Edward (Words, Facts, and Phrases: A Dictionary of Curious Matters, 1882) had this to say about wretchlessness:
This word occurs in the seventeenth article of the Church of England. It is quoted by John Earle in his Philology of the English Tongue  as a curious instance of the change of form in words. He says, "To understand this word we have only to look at it when divested of its initial w, and then to remember than an ancient Saxon c at the end of a syllable commonly developed into tch. In this way, we get back to the verb to reck, so that wretchlessness really means recklessness, or caring for nothing, although the words look so unalike."
Those kooky Saxons.