By the Gospel, too, you are being saved, if you hold to the understanding that I preached to you, lest you believe in vain
Other versions
King James Version
By which also ye are saved, if ye keep in memory what I preached unto you, unless ye have believed in vain. English Standard Version
and by which you are being saved, if you hold fast to the word I preached to you--unless you believed in vain.New International Version
By this gospel you are saved, if you hold firmly to the word I preached to you. Otherwise, you have believed in vain.