Parashat Bo tells of the final three plagues that Hashem brought upon Egypt, culminating with the final plague, the plague of the firstborn, which led Pharaoh to permit Beneh Yisrael to leave Egypt. Already before the eighth plague, the plague of locusts, Pharaoh's servants urged him to yield, to allow Beneh Yisrael to leave and thereby avoid further devastation in the country. Pharaoh summoned Moshe, and expressed his willingness to let the people leave. But when Moshe insisted that the entire nation leave, Pharaoh angrily sent him away, insisting that only the adult males would be permitted to go. Later, after the plague of darkness, Pharaoh summoned Moshe and said he would allow all Beneh Yisrael to leave – but demanded that the animals remain in Egypt. Moshe replied, "Even you will place in our hands sacrifices and offerings for us to prepare for Hashem our G-d, and also our own cattle with come with us, not a single hoof will remain, for we will take from it to serve Hashem our G-d" (10:25-26). In response to Pharaoh's demand that Beneh Yisrael leave behind their cattle, Moshe declared that "not a single hoof" would stay behind, and, moreover, Pharaoh would even give Beneh Yisrael his own animals for them to offer as sacrifices for Hashem. The Malbim (Rav Meir Leibush, 1809-1879) makes an insightful observation regarding the words chosen by Moshe in this response to Pharaoh. Moshe said about Beneh Yisrael's cattle, "Yelech Imenu" – that the animals "will go with us." The implication is that the animals would not need to be taken, but would rather join the people on their own. The Malbim explains this nuance by noting the story told in the Book of Melachim I (chapter 18) of the prophet Eliyahu. Eliyahu challenged the prophets of the pagan god Ba'al to a "contest" on Mount Carmel, whereby they would each offer a bull as a sacrifice – the prophets would sacrifice to Ba'al, and Eliyahu, of course, to G-d. The sacrifice that would receive a response would prove which of them is correct. G-d responded to Eliyahu's sacrifice with a fire that descended from the heavens, thus demonstrating the truth of Hashem and the fallacy of idol-worship. The Midrash teaches that at the beginning of this process, the prophets of Ba'al chose one of the two bulls as their sacrifice, but the bull did not want to go with them. It refused to be used as a sacrifice for idolatry. Eliyahu approached the animal and explained that it would be helping to create a Kiddush Hashem (glorification of Hashem's Name), as this sacrifice would receive no response, whereas Eliyahu's sacrifice would be responded to with a heavenly fire. The bull then agreed, assured that its role was indeed valuable and significant. The other bull, by contrast, needed no convincing, and went happily and enthusiastically to be sacrificed by Eliyahu for the purpose of bringing honor and glory to Hashem. Similarly, the Malbim explains, Moshe told Pharaoh that Beneh Yisrael's animals would go on their own out of Egypt, eager to be offered as sacrifices to Hashem. They would not need to be taken – they would just go, driven by the desire to serve G-d. The Malbim writes that this is indicated by the text for us to learn from the animals' example. Religious observance often demands sacrifices, requiring us to refrain from things which we want to do, and to give of our time, money and energy, for the sake of serving the Almighty. Moshe's description of Beneh Yisrael's cattle is meant to teach us to make these sacrifices enthusiastically, recognizing the great value of serving Hashem. There is no greater privilege than living as Hashem's servants, bringing Hashem honor and glory, and it is with this mindset, with this spirit and enthusiasm, that we are to make the sacrifices – however difficult – that Torah life often requires.