Rut and the Seeds of Mashiach

Because of two good 'doves' [pure and righteous Rut the Moavite and Naamah the Ammonite], the Holy, Baruch Hu, had mercy on two great nations [Ammon and Moav] and did not destroy them.  (Talmud)
There were two women from whom were built the seed of Yehudah and from whom descended Melech David, Melech Shlomo, and the Melech Mashiach. Tamar and Rut, both acted properly in order to do good with the dead. (Zohar)
The Tribes were occupied with the sale of Yosef, Yosef was occupied with is sackcloth and fast, Reuven was occupied with this sackcloth and fast, and Yaakov was occupied with his sackcloth and fast, and Yehudah was occupied with taking a wife.  And the Holy One, Baruch Hu, was occupied in creating the light of the Melech Mashiach.  (Midrash)