And there is no other God besides me, a righteous God and a Saviour.
The passage from which this verse comes is a wonderful Gospel passage speaking about many people coming to plead with God for salvation. Many of the people spoken about had their idols of wood and stone, but they would come to the Jewish people to see if their living and true God would accept them. God's answer was that of course he would: "Turn to me all the ends of the earth! For I am God, and there is no other." (verse 22) God wants all people to be saved.
But look at how God describes himself in verse 21: "a righteous (just) God and a Saviour." One meaning of God being a righteous or just God is that he can be trusted; he speaks the truth and tells only what is right (45:19). But one other great thing about this text is the fact that God has a way of being just and a Saviour at the same time.
We see this in a clearer way in the New Testament when God's perfect Son, the Lord Jesus Christ, died on the cross. He took all the sin of all who put their trust in him and paid the penalty for that sin (God is just and he must judge sin) and so he became at the same time the Saviour. God is just so does not demand any more punishment for the sin of those for whom Jesus died. That is Gospel, good news, and it is the message God wants all people to hear. It is true.
Dear Lord, as I thank you for Jesus, help me to spread this good news. Amen.