16 Only let us hold true to what we have attained.

16 Nevertheless, whereto we have already attained, let us walk by the same rule, let us mind the same thing.

16 But we must hold on to the progress we have already made.

16 Nevertheless, to the degree that we have already attained, let us walk by the same rule, let us be of the same mind.

16 But we should continue following the truth we already have.

16 only, whereunto we have attained, by that same rule let us walk.

16 But whereto we have attained, let us walk in the same steps.

16 However, we should be guided by what we have learned so far. 

16 In any case, we should live up to whatever truth we have attained.

16 Only let us hold fast to what we have attained.

16 Only to what we have attained, to the same hold on.

16 Only let us live up to what we have already reached.

16 however, let us keep living by that same standard to which we have attained.