As far as I know, the phrase beyond my ken is the only way the word is used today. AHD says it's From Middle English kennen (influenced by Old Norse kenna, to know), from Old English cennan, to declare.] I seem to recall reading here and there that it was used as a verb in 19th.-early 20th. C. in the U.S. ... though come to think of it, I believe it was about people in Appalachia who still had strong ties to their Scottish roots, where the verb usage was (is?) common.