The god has warned against the sin of Idolatry and cured Israel from this sin. Once the Israelites returned from exile and rebuilt the temple, they never turned away from the true god. Ezekiel gave clear instructions against the sin of idolatry and told his followers of the extreme consequences of this sin.
It was important for his nation to know of the horrendous consequences so they could keep away from this sin and abide by the law of God. As in the books before and the books that come after, there has been strict laws against the sin of idolatry.