John Gill Commentary Psalms 35:7

"For without cause have they hid for me their net [in] a pit; Without cause have they digged [a pit] for my soul." — Psalms 35:7 (ASV)

For without cause have they hid for me their net [in] a pit ,
&c.] This is said in allusion to the custom of digging pits, and putting nets into them, for the catching of wild beasts; and covering them with straw or dust, or such things, as Jarchi observes, that they might not be discerned; and which means the secret and crafty methods taken by David's enemies to ensnare him and destroy him; though he had given them no cause to use him in such a manner; which is an aggravation of their sins, and a reason of the above imprecations, as well as of what follows:

And in the same manner, and without any just cause, Christ and his members have been treated by wicked men, and therefore their damnation is just, and will be inevitable:

[which] without cause they have digged for my soul ;
which is added for further explanation's sake, and to aggravate their sin, and to show the justness of their punishment.