I know I have the body of a weak, feeble woman; but I have the heart and stomach of a king, and a king of England too.
At the time of Elizabeth's reign, women were considered to be the weaker sex and definitely not suited to the strategy and execution of complex war plans. By confronting this stereotype herself Elizabeth boosted the morale of her troops and also strengthened her own position to prevent mutiny or an attempt on the throne from within. Elizabeth was not typically feminine in behavior, refusing to marry or bear heirs in favor of devoting herself to her country, and it was important that her troops also viewed her as a monarch not as a Queen. Her admission that she would need to draw on what were viewed as typically more manly characteristics also gave reassurance that she was aware of exactly the strength required to lead her armies to victory.
...we shall shortly have a famous victory over these enemies of my God, of my kingdom and of my people.
There were many challenges to the kingdom and by aligning herself with God Elizabeth also succeeded in putting her enemies squarely against God. There were huge divides between Catholics and Protestants especially with the relatively new Church of England; the Plantagnets threatened the kingdom from within, their Catholic line constantly plotting against Elizabeth. The threat from Europe, led by Spain, again threatened the very existence of the nation and also brought more challenges to the religious stability of England. Elizabeth gives confidence to her troops by promising victory and also by clearly stating that they cannot be anything but victorious with God on their side.