Congregation ... assembly - Each of the Hebrew words signifies the people in a collected body. It does not appear that there is any difference between them in the connection in which they are here used.
Related Commentaries of Leviticus 4:13
Leviticus 4:13
13 And if the whole congregation of Israel sin through ignorance, and the thing be hid from the eyes of the assembly, and they have done somewhat against any of the commandments of the LORD concerning things which should not be done, and are guilty;