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Honi the Circle Maker
Once while Honi HaMa’agal (the circle-maker) was walking down the road, he saw a man planting a carob tree. Honi asked, “How many years will it take for this tree to bear fruit” The man answered that it would take 70 years. Honi said, “Are you so healthy that you expect to live that long to enjoy its fruit?” The man answered, “I found a fruitful world, because those who lived before me planted trees for me. In the same way, I shall do this for my children.”
( Babylonian Talmud, Ta’anit 23a)
Shimon bar Yochai
Shimon bar Yochai: “if you are holding a sapling in your hand and someone says that the Messiah has drawn near, first plant the sapling, and then go and greet the Messiah.” Avot d’Rebbe Natan 31b