Albert Barnes Commentary Psalms 71:11

"Saying, God hath forsaken him: Pursue and take him; for there is none to deliver." — Psalms 71:11 (ASV)

Saying, God has forsaken him — That is, God has given him over; he no longer protects him; he regards him as a wicked man, and we shall therefore not only be “safe” in our attempts upon his life, but we shall be “justified” in those attempts.

Persecute and take him — It can be done safely now; it can be done with propriety.

For there is none to deliver him — He has no one now to whom to look; no one on whom he can rely. Abandoned by God and by man, he will be an easy prey. Compare the notes at Psalms 41:7-8.