For this reason, it is necessary for us to observe more thoroughly the things that we have heard, lest we let them slip away
Other versions
King James Version
Therefore we ought to give the more earnest heed to the things which we have heard, lest at any time we should let them slip. English Standard Version
Therefore we must pay much closer attention to what we have heard, lest we drift away from it.New International Version
We must pay more careful attention, therefore, to what we have heard, so that we do not drift away.