The Daily Ma’amar of our Rebbe Rav Eliezer Berland shlit”a, courtesy of the “Hashem Hu HaElokim” leaflet:
Moshe Rabbeinu gave over to the spies all the secrets and intentions of Leah – the initial letters of “to spy out the Land” (Bamidbar 13:16), for Leah is the aspect of the sun and Rachel is the aspect of the moon.
And he said to the spies: “Are there trees in it or not?” Could it be that Moshe did not know that it had trees in it? Behold 10 people brought one cluster [of grapes], and one person carried a single fig, and one carried a single pomegranate, and so the Land of Israel is praised in all Seven Species, in all the types of fruit in the world. If so, what is this question of Moshe – “Are there trees in it or not”?!
Rather, the Zohar says in [Parashat] Beshelach Lecha: “Tree” – meaning “the Tree of Life,” and the Land of Israel is called the “lands of the living,” as King David, may peace be upon him, said (Tehilim 116:9): “I shall walk before Hashem in the lands of the living,” because here the illumination of the Tree of Life is drawn.
And therefore, Hashem said: “Send for yourself” – for your need, for your sake, the spies, who shall draw to the Land of Israel the illumination of the Tree of Life, which is called “Sun (Chamah)” and remove it from the aspect of “Moon (Levanah – Sihara),” and therefore only Yehoshua, who was an aspect of moon (sihara) entered.
However, they walked “the expanse at the approach to Chamat (Rechov Levo Chamat)” (Bamidbar 13:21) – the initial letters of RaCheL, and only used the intentions of Rachel, and did not succeed in drawing the illumination of the Tree of Life which is called “Chamah.”
And therefore, the Tosofot say [Baba Batra 119b]: That Tzelafchad came after the sin of the spies. The Zohar explains in Shelach Lecha: That Tzelafchad wished to cause the Tree of Life to overwhelm the Tree of Knowledge through his gathering wood, and therefore did this on the day of Shabbat, in order to draw the light of Shabbat – that then Israel and Rachel are face-to-face – to the entire week, as it was in the days of King Shlomo – that everything was face-to-face, and only Keter (Crown) opposite Keter was lacking, because Shlomo only accomplished that Keter of Rachel would be opposite Chochma (Wisdom) of Zeir Anpin (the “Small Face”), and, therefore, there still has not been the revival of the dead and the Third Temple, which is a Temple of fire, still has not been built.
And this is what Rechavam wished for (according to I Melachim 12:14): That in the month of the astrological sign of “Akrav (Scorpio)” the Temple of fire would be built anew, as it is written (Shemot 15:17): “You will bring them and plant them on the mount of Your heritage, the foundation of Your dwelling place that You, Hashem, have made – the Sanctuary, my Lord, that Your hands established,” that this will be a Temple of fire, speedily in our days, Amen Netzach Selah Va’ed.
 To explain, in the time of King Shlomo, the unification of Zeir Anpin with Rachel was such that on weekdays it was on the same level as Shabbat, however, only the aspect of face-to-face was lacking at the level of Keter, which will only be the case in the final redemption, this being the rectification of the blemish of the moon, after the moon accused and said, “Can two kings share one crown?”