The form of the Greek phrase makes it somewhat difficult to translate. I do not think that the phrase 'in the sleight of,' &c., is in connection with 'tossed and carried about,' but, in sense, with 'that teaching.' The cheating, as of dice-players, and still more methodic craft, characterized the teaching. 'In the sleight of men' marks the power and character of the teaching. What I have given is literal, and is sufficiently clear: 'that' is emphatic.
The word 'supply' in Greek has the emphatic article and it might read 'that supply, [which is] according to.' The article denotes a known supply from Christ. sufficiently known to be referred to, to which also the 'from whom' lends force.