'Lose Heart' in the Bible

Now Jesus was telling the disciples a parable to make the point that at all times they ought to pray and not give up and lose heart,

Because of this, [since we] have this ministry, just as we have been shown mercy, we do not lose heart,

Therefore we do not lose heart, but even if our outer person is being destroyed, yet our inner [person] is being renewed day after day.

but let us not lose heart in doing good; for in due time, if we do not faint, we shall reap.

So I ask you not to lose heart at my sufferings on your behalf, for they are your glory and honor.

Fathers, do not exasperate your children, so that they will not lose heart.

And as for [the rest of] you, believers, do not grow tired or lose heart in doing good [but continue doing what is right without weakening].

For consider Him who endured such hostility from sinners against Himself, so that you won’t grow weary and lose heart.

and you have forgotten the exhortation which reasons with you as with children, "My son, do not take lightly the discipline of the Lord, nor lose heart when you are reproved by him;