'Be Strong' in the Bible

But you should be alert at all times, offering earnest prayers, so that you will be strong enough to escape all these things that will happen, and to appear [acceptable] in front of the Son of man [on that day]."

But I prayed earnestly for you, that your faith would not fail [to be strong]. And when you have turned back [i.e., from going astray briefly], provide [spiritual] support to your brothers."