"We must strive eagerly to attain that rest" (4:11): and this word "strive eagerly" is the same as that in Joshua 4:10, where we read that "the people hasted and passed over" the Jordan. From this we see that faith is not a substitute for effort, and that effort can never be a substitute for faith.
The truth about practical holiness has suffered at times, because it has been represented as something that needs not the effort of man for its realization. This, however, is not true. Just because we are rational and moral beings, we have some responsibility for our own sanctification.