IF by our endurance we press on in well-doing. For you have need of endurance, so that you may do the will of God and receive what is promised. You need to endure so that you can do the will of God so that you can obtain what is promised. Those are the two kinds of texts you find in the Bible concerning endurance. The other kind urges us to endure so that we will be saved.
Endurance is a gift and endurance is a duty.
And these are not in conflict. When dealing with a holy and sovereign God these are not contradictions. In one sense the two different kinds of Scriptures because they have two different purposes. But in another sense they are perfectly one. Consider their different purposes.