Midrash su Salmi 21:5

"The righteous shall flourish like the palm tree" (Ps. 92:12). Just as this palm tree is beautiful in all its appearance, and all its fruits are sweet and good, likewise the son of David is beautiful in his appearance and in his glory, and all his deeds || are good and sweet before the Holy One, blessed be He, as it is said, "The righteous shall flourish like the palm tree: he shall grow like a cedar in Lebanon" (ibid.). Just as this cedar has very many roots beneath the earth, and even if the four winds of the world came against it, they could not move it from its place, as it is said, "He shall grow like a cedar in Lebanon. They that are planted in the house of the Lord" (Ps. 92:12, 13). In the future when the Holy One, blessed be He, will gather Israel from the four corners of the world, just like this gardener who transplants his fir trees from one garden-bed to another garden-bed, likewise in the future will the Holy One, blessed be He, gather them from an impure land and (plant them) in a pure land, as it is said, "They that are planted in the house of the Lord" (ibid.). Like this grass, they shall blossom and sprout forth in the Temple, as it is said, "In the courts of our God they shall flourish" (ibid.).