'Cultivate' in the Bible

So then, my dear ones, just as you have always obeyed [my instructions with enthusiasm], not only in my presence, but now much more in my absence, continue to work out your salvation [that is, cultivate it, bring it to full effect, actively pursue spiritual maturity] with awe-inspired fear and trembling [using serious caution and critical self-evaluation to avoid anything that might offend God or discredit the name of Christ].