Adam Clarke on 2 Peter 2:12

But these, as natural brute beasts - 'Ὡς αλογα ζωα φυσικα· As those natural animals void of reason, following only the gross instinct of nature, being governed neither by reason nor religion.

Made to be taken and destroyed - Intended to be taken with nets and gins, and then destroyed, because of their fierce and destructive nature; so these false teachers and insurgents must be treated; first incarcerated, and then brought to judgment, that they may have the reward of their doings. And thus, by blaspheming what they do not understand, they at last perish in their own corruption; i.e. their corrupt doctrines and vicious practices.