One or Two: Mashiach ben Yosef and Mashiach ben Yehuda

For what is the nature of this eulogy? The Gemara answers: Rabbi Dosa and the Rabbis disagree concerning this matter. One said that this eulogy is for Messiah ben Yosef who was killed in the war of Gog from the land of Magog prior to the ultimate redemption with the coming of Messiah ben David. And one said that this eulogy is for the evil inclination that was killed. The Gemara asks: Granted, according to the one who said that the lament is for Messiah ben Yosef who was killed, this would be the meaning of that which is written in that context: “And they shall look unto Me because they have thrust him through; and they shall mourn for him, as one mourns for his only son” (Zechariah 12:10). However, according to the one who said that the eulogy is for the evil inclination that was killed, does one need to conduct a eulogy for this? On the contrary, one should conduct a celebration. Why, then, did they cry? The Gemara answers: This can be understood as Rabbi Yehuda taught: In the future, at the end of days, God will bring the evil inclination and slaughter it in the presence of the righteous and in the presence of the wicked. For the righteous the evil inclination appears to them as a high mountain, and for the wicked it appears to them as a mere strand of hair. These weep and those weep. The righteous weep and say: How were we able to overcome so high a mountain? And the wicked weep and say: How were we unable to overcome this strand of hair? And even the Holy One, Blessed be He, will wonder with them, as it is stated with regard to the eulogy: “So says the Lord of hosts: If it be wondrous in the eyes of the remnant of this people in those days, it should also be wondrous in My eyes” (Zechariah 8:6). The Sages taught: To Messiah ben David, who is destined to be revealed swiftly in our time, the Holy One, Blessed be He, says: Ask of Me anything and I will give you whatever you wish, as it is stated: “I will tell of the decree; the Lord said unto me: You are My son, this day have I begotten you, ask of Me, and I will give the nations for your inheritance, and the ends of the earth for your possession” (Psalms 2:7–8). Once the Messiah ben David saw Messiah ben Yosef, who was killed, he says to the Holy One, Blessed be He: Master of the Universe, I ask of you only life; that I will not suffer the same fate. The Holy One, Blessed be He, says to him: Life? Even before you stated this request, your father, David, already prophesied about you with regard to this matter precisely, as it is stated: “He asked life of You, You gave it to him; even length of days for ever and ever” (Psalms 21:5).

The nation of Israel is comparable to a person with twelve (primary) limbs/organs... There are two limbs that are primary, and therefore have the potential to lead the other organs, the heart and the brain. The kingship of Yehuda corresponds to the head, and the kingship of Yosef to the heart...

Now, it is known that the seat of the Neshama is in the brain/mind, and the Neshama is more G-dly than the heart (which relates to ruach, a lower level of the soul).

So too, with regard to the kingship of Yehuda. When Jewish kingship is in its prime then the Jews attain a lofty level and there is only one king from the tribe of Yehuda. After all, the nation of Israel is one being, and it is appropriate that there be one king uniting everyone.

However, when they aren't worthy, the kingship is split between Yehuda and Yosef/Ephraim...

But the king from Yosef will not last, and the Mashiach ben Yosef will be killed during the war of Gog and Magog...

Mashiach ben David, however, will live on... This relates to the life that Mashiach ben David requests and is granted.

(16) And you, O mortal, take a stick and write on it, “Of Judah and the Israelites associated with him”; and take another stick and write on it, “Of Joseph—the stick of Ephraim—and all the House of Israel associated with him.” (17) Bring them close to each other, so that they become one stick, joined together in your hand.