The destruction of the Temple was essentially caused by forgetfulness, that was caused by the evil eye that was jealous of Israel and led them astray. This is why we must weep during the Three Weeks, especially on the 9th of Av, over the destruction of the Temple. “My eye, my eye, pours out water” (Lamentations 1:16). As King David said after Absolom’s evil eye fell on him, “Then perhaps Hashem will see my eye,” (II Samuel 16:12), where Rashi comments, “the tears of the eye.” We also read there, “David … went up weeping … and all the people who went up with him … were weeping” (ibid 15:30).
This correspond to, “My tear was my bread … These i remember and I pour out my soul” (Tehillim 42:4). Through tears, we subdue the veil eye, which causes forgetfulness. Then, after weeping profusely, we attain memory, as in “These I remember.”
The kinot (lamentations) of the Three Weeks and the 9th of Av are a tikkun (soul rectification), in order to merit t’shuva (repentance). This is why we conclude the reading of Eikha (the Book of Lamentations) repeating the verse, “Hashiveinu (Return) us, Hashem, to You.”
By subduing the evil eye with our tears, we can erase forgetfulness, allowing us to remember Olam HaBa (The World to Come), through which we will be able to return to Hashem. Hence, our main intention in weeping during the reading of the kinot is in order to arouse Hashem’s compassion to bring us back to Him.
Based on Likutei Halakhot, Orach Chaim, Birkhot haR’ia u’Vrakhot P’ratiot 5, available in Hebrew/English Edition Orach Chaim II, Part II, Author: Reb Noson -Translation – Keren Yisrael Ber Odesser.