Adam Clarke on Psalms 10:15

Break thou the arm - Destroy his power, deprive him of his influence, that he may be no longer able to oppress.

Seek out his wickedness till thou find none - All his public haunts and private ways shall be investigated; thou wilt bring all his villanies to light, and continue to inflict punishment, while there is a crime to punish. Or, "Continue to judge and punish transgressors, till not one is to be found." This agrees with the following verse.