From Bayly:

1. If, when thou art about to pray, Satan shall suggest that thy prayers are too long, and that therefore it were better either to omit prayers, or else to cut them shorter, meditate that prayer is thy spiritual sacrifice, wherewith God is well pleased (Heb. xiii. 15, 16;) and therefore it is so displeasing to the devil, and so irksome to the flesh. Bend therefore thy affections (will they, nill they) to so holy an exercise; assuring thyself, that it doth by so much the more please God, by how much the more it is unpleasing to thy flesh.

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Eph. 6:11 Put on the whole armour of God, that ye may be able to stand against the wiles of the devil.

Ja. 4:7 Submit yourselves therefore to God. Resist the devil, and he will flee from you.

Heb. 13:15 Through him then let us offer up a sacrifice of praise to God continually, that is, the fruit of lips which make confession to his name. 16 But to do good and to communicate forget not: for with such sacrifices God is well pleased.

I Pt. 5:8 Be sober, be vigilant; because your adversary the devil, as a roaring lion, walketh about, seeking whom he may devour: 9 Whom resist stedfast in the faith, knowing that the same afflictions are accomplished in your brethren that are in the world.