Psalms 37:15

Their sword shall enter into their own heart,.... As Saul's did into his, 1 Samuel 31:4;

and their bows shall be broken; the meaning is, that their efforts shall be fruitless, and their attempts in vain; the mischief they have contrived and designed for others shall fall upon themselves; see Psalms 7:15; and therefore the saints should not be fretful and envious.