The bronze script of character Thing ischaracter Official - 吏 (Post 540). In ancient time, this character means official too. Official is the person who do the daily work, the things. So the two characters are from the same origin.
The big seal script of the character is
The small seal script of the character is
The clerical script of the character is
The pinyin of the character is Shi4.
事 is lower level official, but may be higher than 吏. Besides, 事 is most used for Things now, not the person who execute the Things.