Jamieson, Fausset and Brown on 2 Samuel 24:14

14. David said, ... Let us fall now into the hand of the Lord--His overwhelming sense of his sin led him to acquiesce in the punishment denounced, notwithstanding its apparent excess of severity. He proceeded on a good principle in choosing the pestilence. In pestilence he was equally exposed, as it was just and right he should be, to danger as his people, whereas, in war and famine, he possessed means of protection superior to them. Besides, he thereby showed his trust, founded on long experience, in the divine goodness.

2Sa 24:15-25. His Intercession to God; the Plague Ceases.