Komentaryong Sumisipi para sa Josue 11:18

החלצו מאתכם, “mobilize from amongst yourselves, etc.” It is as if Moses had said: “gird your pioneers, your vanguard, (with their swords).” The words used here reflect an eagerness on the part of Moses to discharge his part in this commandment although G’d had told him that its fulfillment would bring about his death shortly thereafter. Tanchuma Mattot 4 points out the contrast between Moses and Joshua in this matter. When Joshua faced 31 Canaanite kings he said to himself: “if I slay them I will die shortly thereafter just as Moses died shortly after the Midianites were defeated.” What did Joshua do? He commenced with attacking one of the Canaanite kings and then delayed following up on his success as we know from Joshua 11,18: “Joshua was engaged for many years in battling all these kings.” When G’d observed this He told him: “because you did this in order to prolong your life I will deduct 10 years from the life span I had allocated to you originally. You should have lived to 120 years as did your teacher Moses. Now you will live to be only 110 years.” This is the meaning of Proverbs 19,21: “Many designs are in a man’s mind, but it is the Lord’s plan that is accomplished.“

A second way [of explaining] the continuation of these verses is, that “Elohim” only means Judge, and it is not yet explained in what judgment the Holy One, blessed be He, judged. Therefore, it seems to me that this judgment refers to the preceding verse where it says, Now you will see what I will do to Pharaoh. Our Sages of blessed memory explained (Sanhedrin 111), “but not what will be done to the kings of the seven nations.” The word “kings” seems redundant because it could have simply said “not what will be done to the seven nations.” (And in Shemot Rabbah 5:23) it concludes “and you will not see what I will do in the war against the 31 kings.”
This is difficult: why do we need this count? Do we not already know that Israel fought against 31 kings? And there’s another difficulty: why does it say Now you will see what I will do to Pharaoh — why do I need the word now? Although I explained the meaning of “now” at the end of Parshat Shemot, nevertheless there are additional divine interpretations to explain it in another way, namely:
The Holy One, blessed be He, said to Moses, I am the Lord who was, is, and will be. For all flesh and blood cannot be certain to fulfill their promises, since the spirit leaves him and he is gone and cannot fulfill his promise. Therefore, he must fulfill it immediately. And if not, then justifiably those who were promised complain about why the pronouncement of his word was not done quickly, for if not now, when? But I exist eternally, equally throughout all times, therefore the forefathers did not complain but waited and anticipated when the word of God would come, and they were confident that it would ultimately be fulfilled.
But you complained that My words were not fulfilled immediately, therefore all the more so you would complain about the wars against the 31 kings, because those wars would necessarily be prolonged, as it is written Joshua waged war with all those kings for a long time (Joshua 11:18). For Israel could not inherit all the land quickly lest the beasts of the field multiply against them, but rather [the seven nations] would be driven out gradually.
And because it is your way to complain when a promise is not fulfilled quickly, therefore I am penalizing you that justifiably you will not see the prolonged war against the 31 kings, except for the war against Pharaoh who is a single king, and you can see now — meaning immediately — what I will do to Pharaoh. Only that you will see. And the main exclusion comes from the word now meaning you will only see what is done immediately, but not something that will not be done now but only after many days, such as the war against 31 kings — that you will not see.
And this is what is meant by and My name, the Lord which indicates that I exist eternally and My promise will ultimately be fulfilled, but they did not yet know this, and they waited to see [the fulfillment of] My words as mentioned.

A Midrashic approach (Tanchuma Metzora 6): Seeing that the woman who is a Niddah has to observe at least seven days in that state how can three days be considered “many,” seeing seven days is much more than three days? Furthermore, we find in Kings I 18,1 that the prophet Jeremiah speaks of: “it was during these many years when G’d spoke to Elijah in the third year saying to him: ‘show yourself to Achav and I will bring on rain.’” The fact is that this did not take place after three years but it was only a single month after the first year full year of the drought had been completed! The drought began at the beginning of the last month of the year during which Elijah had proclaimed it; it lasted the entire second year, i.e. at the end of the second year no rain had fallen for 13 months. [When G’d told Elijah to reveal himself to Achav, one month had passed of the third year, so that altogether the famine had been in effect for only 14 months. Ed.] Seeing that the period under discussion was one in which hardship and discomfort was experienced, even a relatively short period was described as “many years;” the same is true here. Seeing that the period during which the woman remains relatively isolated and suffers indisposition is an unpleasant period for her, the Torah describes even three days of such a period as ’many days.’