The phrase "the day" is an idiom that refers to a specific event happening. AT: "You have done what you have promised" (See: [[rc://en/ta/man/translate/figs-idiom]])
# now let them become like me
This is a request for Jerusalem's enemies to suffer as the people of Jerusalem have. AT: "now let them suffer like me" (See: [[rc://en/ta/man/translate/figs-explicit]])
# Let all their wickedness come before you
This is a request for Yahweh to judge Jerusalem's enemies for their wickedness. The phrase "come before you" is an idiom. AT: "Pay attention to all of the wickedness they have committed" or "Judge them for all of their wickedness" (See: [[rc://en/ta/man/translate/figs-idiom]])
# deal with them as you have dealt with me
This is a request for Yahweh to punish Jerusalem's enemies as he punished the people of Jerusalem. AT: "punish them as you have punished me" (See: [[rc://en/ta/man/translate/figs-explicit]])
# my heart is faint
Here the "heart" represents the whole person. AT: "I am faint" (See: [[rc://en/ta/man/translate/figs-synecdoche]])