God is frustrated with His people. He purchased them and cared for them, but they have not listened to Him. As a parent, I have felt some of this same frustration. God is trying to lead them along a good path. One that will bless them and do them good. But they continue to seek other roads that lead to destruction. God has done everything He can to bring them back, but they have refused to listen.

If you listen to this prophecy, you can feel His frustration. He does not want to continue to correct them. He doesn't like seeing them in pain. But He is at a loss to know what else He could do to bring them back onto the paths of peace.

The picture here is of a trial. The prosecutor is laying out his case. He calls heaven and earth to hear the evidence. God has blessed them, and they have forgotten Him. Not only have they forgotten Him, but they have turned to false gods (adultery). They have acted like a faithful wife, but their words and actions are merely acts, without substance.

Instead of seeking a judgment against them, God pleads with them to accept a settlement: Isaiah 1:18-20

18 “Come now, and let us reason together,” Says the Lord,
“Though your sins are as scarlet,
They will be as white as snow;
Though they are red like crimson,
They will be like wool.
19 “If you consent and obey,
You will eat the best of the land;
20 “But if you refuse and rebel,
You will be devoured by the sword.”
Truly, the mouth of the Lord has spoken.

In Dt. 32, when Moses was giving Israel his final words of instruction, Moses calls on the earth and the heavens to witness what he was telling them. Not only is Isaiah using the same format for emphasis, Isaiah is reminding the Israelites of the warning that God gave them in Dt. 32.

“Give ear, O heavens, and let me speak; And let the earth hear the words of my mouth.”

Moses told them of all the curses that would come upon them if they forsook the Lord God.

TRANSLATION:
בָּנִים֙ גִּדַּ֣לְתִּי וְרוֹמַ֔מְתִּי וְהֵ֖ם פָּ֥שְׁעוּ בִֽי
I have strengthened sons and made them great
And they have rebelled against me.

The idea here is not just that God had sons, but He made His sons strong and great . . . and in their strength they left God (no longer thinking that they needed Him) and they left God. The sense of betrayal is thick in this verse.

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The word for rebelled or left is Pasha (פָּשַׁע), meaning to fall away/ break away (from just authority), i.e. trespass, apostatize, quarrel:—offend, rebel, revolt, transgress

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NOTE: People often abandon God when they feel strong, but call out to Him when they are in trouble or feel weak. And then, later, when they are feel stronger again, they forget about Him and walk away:

"For they have turned their back to Me,
And not their face;
But in the time of their trouble they will say,
‘Arise and save us.’"

People even go so far as to believe that saving them is God's job and they feel like God let them down if He does not save them when they are in trouble, even though the emergency is the result of their actions.

Listen, O heavens, (Shimu Shamaim)
and hear, O earth (Ha-Azini Eretz)