KJV - That thou mightest know the certainty of those things, wherein thou hast been instructed.

ASV - that thou mightest know the certainty concerning the things wherein thou wast instructed.

BBE - So that you might have certain knowledge of those things about which you were given teaching.

WEB - that you might know the certainty concerning the things in which you were instructed.

YLT - that thou mayest know the certainty of the things wherein thou wast instructed.

Notes