Midrash sur Isaïe 25:1

"and the children of Israel went out with a high hand": Scripture hereby apprises us that when the Egyptians were pursuing Israel, they vilified and execrated and cursed, while Israel exalted, praised, and sang a song of glorification to the L rd of the war, as it is written (Psalms 149:6) "the exalting of G d in their throats and a two-edged sword in their hands," and (Ibid. 57:6) "Exalted over the heavens is G d, etc.", and (Isaiah 25:1) "O L rd, You are my G d. I will exalt you. I will praise Your name. For You wrought wondrously. Counsel from afar, enduring faith."

"the L rd will war for you": Not only now, but He will always war for you against your enemies. R. Meir says: The L rd will war for you when you stand still. How much more so when you accord praise to Him! R. Meir says: "the L rd will war for you": He will perform for you miracles and (acts of) strength, and you will stand still. Israel asked Moses our teacher: "What can we do?" He answered: You exalt Him and accord song, praise, grandeur and glory to the Master of wars, viz. (Psalms 149:6) "The praises of G d in their throats", and (Ibid. 57:6) "Be exalted over the heavens, O G d; over all the earth, Your glory", and (Isaiah 25:1) "O L rd, You are my G d. I will exalt You. I will praise Your name for You wrought wondrously. Counsels from afar, enduring in faith." At that time Israel opened their mouths in song, viz. (Exodus 15:1) "I shall sing to the L rd for He is exalted (over all the) exalted."