Isaiah is the first and biggest of the major books of the prophets. There are 11 books of prophecy, 5 of them are “major”, and 6 are “minor”. This doesn't mean that some are more important than others (they are all important), but that some are longer and some are shorter.
8 For Jerusalem stumbled,
And Judah is fallen,
Because their tongue and their doings
Are against the Lord,
To provoke the eyes of His glory.
9 The look on their countenance witnesses against them,
And they declare their sin as Sodom;
They do not hide it.
Woe to their soul!
For they have brought evil upon themselves.
10 Say to the righteous that it shall be well with them,
For they shall eat the fruit of their doings.
11 Woe to the wicked! It shall be ill with him,
For the reward of his hands shall be given him.
In this chapter, Isaiah prophesies what will happen to Judah because they disobeyed God and didn't repent. In verse 8, we find out why God has to judge Judah because “their tongue and their doings Are against the Lord”. Judah had provoked God to punish them.
In verse 9, we find out what Judah did to provoke God. It says that they declared their sin as Sodom, and they don't hide it. Sodom was a city that was filled with wickedness, and they were showing off about it. Remember what happened to Sodom? Their city was destroyed by fire from heaven, so parading your sin about and calling it good is serious, and God will punish it.
In verse 10, we are encouraged that it will be well with the righteous because they will be rewarded for their good deeds. However, we cannot be righteous without Jesus forgiving us.
On the other hand, it will be bad for the wicked because they will be judged according to their deeds.
If you want to be counted among the righteous and not the wicked, we need to believe in Jesus and ask Him to forgive us of our sins.