Psalm 35 has been omitted from the lectionary, probably as a ‘special interest’ poem — in this case for those who have been slandered or victim of deceit and such injustices. Hopefully most readers will not suffer such pain too often and may not identify with the psalmist and the song; but it does happen.
As noted in relation to other songs by David like Psalm 52 and 34, the historical setting and David’s harsh experience at the hands of both slanderers and King Saul are important.
The psalmist early recognises that the best response is to seek wisdom and any remediation required from the source of all love and justice, rather than taking an eye for an eye. There’s no doubt that David hopes for the downfall of his opponents. Significantly, though, he is sympathetic to the plight of his enemies when they were sick, wearing sack-cloth, fasting, praying and regarding them just like good friend or family. (vs 13, 14)
The psalm highlights the devastation unguarded words can cause in the lives of others, and recommends the habit of speaking the truth in love. (Eph. 4:15)
Each of three sections concludes (verses 10, 18, 28) in a declaration of trust in divine goodness.
There are a couple of settings around, neither common nor antiphonal. To my mind, the psalm does not lend itself well to this responsorial style unless the refrain is positive and uplifting. Isaac Everett‘s in The Emergent Psalter, sounding appropriately rather like a Hebrew song (download>), is just that:
Otherwise, a hymn like PFAS 35A (the only suggestion in this book, but with the added attraction of an arrangement by JS Bach) might suffice as a response to the reading.