An oath cannot be broken, even more so when it is the Lord’s. Therefore, the people could be completely assured of what would come to pass.
Instances on Isaiah where it is said that the Lord has sworn an oath are also found in Isaiah 45:23 and Isaiah 62:8.
24 L'Eternel des armées l'a juré, en disant: Oui, ce que j'ai décidé arrivera, Ce que j'ai résolu s'accomplira.