This psalm forms a chiastic structure:
1a) Psa 59:1-5, Defend me + deliver me, O my God, from bloodthirsty men;
1b) Psa 59:6-7, At evening they return + growl like a dog;
1c) Psa 59:8, The LORD shall have all nations in derision;
1d) Psa 59:11, Do not slay them but scatter them by Your power;
central axis) Psa 59:12, “For the sin of their mouth and the words of their lips, Let them even be taken in their pride, And for the cursing and lying which they speak;”
2d) Psa 59:13a, Consume them in wrath that they may not be;
2c) Psa 59:13b, God rules in Jacob to the ends of the earth;
2b) Psa 59:14-15, At evening they return + growl like a dog;
2a) Psa 59:16-17, You have been my defense + refuge in the day of trouble.
Psa 59:9-10 mirrors Psa 59:17, and so my thought is that the final form of this structure will be more complex than I have it here. The central axis, however, describes the wickedness of wrong words. We tend of think of words as a light sin, but wrong words, words which pronounce or agree with lies, or pronounce or agree with cursing, is central matter. Words have creative and prophetic power, to bring to pass the thing spoken, especially if spoken by one in authority. The sin of Satan was to cast doubt on God’s true word. The only power the enemy has over us today is the power we give him if we agree with his lying words.
Put a guard over my mouth today, Lord God, and let all my words convey grace, and agree with truth!