'Wrestling' in the Bible

I urge you, believers, by our Lord Jesus Christ and by the love of the Spirit, to join together with me in your prayers to God in my behalf,

because we have not the wrestling with blood and flesh, but with the principalities, with the authorities, with the world-rulers of the darkness of this age, with the spiritual things of the evil in the heavenly places;

Epaphras, who is one of you, a servant of the Messiah Jesus, sends you his greetings. He is always wrestling in his prayers for you, so that you may stand mature, completely convinced of the entire will of God.

and here is the motive of our toiling and wrestling, because we have our hopes fixed on the ever-living God, who is the Saviour of all mankind, and especially of believers.

Ye have not yet resisted unto blood, wrestling against sin.