en_tn_condensed/2sa/03/35.md

All the people came

This deliberate exaggeration is used to show that the nation of Israel wanted to take care of David in his grief. AT: "Many people came" (See: rc://en/ta/man/translate/figs-hyperbole)

May God do so to me, and more also, if

This is the form of a solemn vow in that time. David is asking God to judge him severely if he eats anything before sunset. Your language many have a way of expressing vows. AT: "I am asking God to punish me if"