The language of these imprecatory psalms is harsh (dashed heads against rock, broken teeth, etc.), but it is justly fierce, corresponding to the depth of wickedness displayed by those who would join the serpent against God.
And in a footnote,
Appeals for and celebrations of God's judgment in the Psalms are not 'less than Christian'..., as any reader of the book of Revelation can see. In fact, descriptions of the horrifying terror of the coming judgment are merciful warnings that invite the wicked to repent, and they glorify God who will demonstrate his wrath and make known his power (Rom 9:22).
James Hamilton, God's Glory in Salvation through Judgment (Wheaton: Crossway, 2010), 288-89.