All things ... alike - not universally; but as to death. Ecc 9:2-10 are made by Holden the objection of a skeptical sensualist. However, they may be explained as Solomon’s language. He repeats the sentiment already implied in Ecc 2:14; Ecc 3:20; Ecc 8:14.
one event - not eternally; but death is common to all.
good - morally.
clean - ceremonially.
sacrificeth - alike to Josiah who sacrificed to God, and to Ahab who made sacrifice to Him cease.