'To hurt,' as mentioned in Revelation 6:6, signifies violation and profanation.

In Revelation 9:4, this signifies perverting the truths and goods of the church by crafty rationalizations from sensory scientific facts and fallacies.

'To be hurt of the second death,' as mentioned in Revelation 2:11, signifies sinking under evils and falsities from hell.

(Odkazy: Apocalypse Explained 9 [4]; Apocalypse Revealed 316)

9591. All this shows what FREE WILL is, namely doing what is good because one freely chooses or it is in one's will to do it, and that those people enjoy that freedom who are led by the Lord.