יְהִ֤י פִסַּת־בַּ֨ר ׀ בָּאָרֶץ֮ בְּרֹ֪אשׁ הָ֫רִ֥ים יִרְעַ֣שׁ כַּלְּבָנ֣וֹן פִּרְי֑וֹ וְיָצִ֥יצוּ מֵ֝עִ֗יר כְּעֵ֣שֶׂב הָאָֽרֶץ׃
願地上五穀豐盛，直到山頂；願其果實搖曳作響，如黎巴嫩的樹木；願他們從城中興旺起來，如地上的青草。
Shenei Luchot HaBerit
I believe there is a profound reason why the formula chosen is one that can refer to either the future or the past. We bless the sacred bread of the past which Adam ate before the sin, and which will once again be available in the future. We have a similar discussion between Rabbi Nechemiah and the sages quoted in Shemot Rabbah, 15 where the sages quote Psalms 72,16 to prove that the word המוציא also refers to the future. The Psalmist says: יהי פסת בר בארץ, "Let abundant grain (in the shape of a piece of bread) be on earth."