# Why do you treat so very lightly this change in your ways?

Yahweh is scolding the Israelites because they changed from one kingdom to another for help but did not rely on God for help.

# lightly

without care or concern

# You will also be disappointed by Egypt

"Egypt will also disappoint you"

# You will also be disappointed by Egypt

"You will be disappointed when Egypt does not protect you"

# just as you were by Assyria

"just as Assyria disappointed you"