Here are two very interesting words to compare. It’s quite possible that you are not aware of the difference or perhaps, of the existence of at least one of these two words:
PASSED is the Past Simple tense of the verb ‘to pass’
PAST is a preposition
In the picture:
He PASSED by the mural on his way home.
OR
He walked PAST the mural on his way home.
The two sentences have the same meaning and the two words have the same pronunciation! 