Our Gemara on Amud Aleph discusses a mystical meditation that is inspired by the blue-like techeiles thread in the tzitzis:
מִפְּנֵי שֶׁהַתְּכֵלֶת דּוֹמֶה לַיָּם, וְיָם דּוֹמֶה לָרָקִיעַ, וְרָקִיעַ דּוֹמֶה לְכִסֵּא הַכָּבוֹד — שֶׁנֶּאֱמַר: ״וַיִּרְאוּ אֵת אֱלֹהֵי יִשְׂרָאֵל וְתַחַת רַגְלָיו כְּמַעֲשֵׂה לִבְנַת הַסַּפִּיר וּכְעֶצֶם הַשָּׁמַיִם לָטֹהַר״, וּכְתִיב: ״כְּמַרְאֵה אֶבֶן סַפִּיר דְּמוּת כִּסֵּא״.
It is because sky-blue dye is similar in its color to the sea, and the sea is similar to the sky, and the sky is similar to the Throne of Glory, as it is stated: “And they saw the God of Israel; and there was under His feet the like of a paved work of sapphire stone, and the like of the very heaven for clearness” (Exodus 24:10). This verse shows that the heavens are similar to sapphire, and it is written: “And above the firmament that was over their heads was the likeness of a throne, as the appearance of a sapphire stone” (Ezekiel 1:26). Therefore, the throne is similar to the heavens. The color of sky blue dye acts as an indication of the bond between the Jewish people and the Divine Presence.
Tosafos quotes a Yerushalmi (Berachos ch. 1) with a slightly different list:
שֶׁהַתְּכֵלֶת דּוֹמֶה לְיָם. וְהַיָּם דּוֹמֶה לַעֲשָׂבִים. וְעֲשָׂבִים דּוֹמִין לָרָקִיעַ. וְרָקִיעַ דּוֹמֶה לְכִסֵּא הַכָּבוֹד. וְהַכִּסֵּא דּוֹמֶה לְסַפִּיר דִּכְתִיב וָאֶרְאֶה וְהִנֵּה עַל הָרָקִיעַ אֲשֶׁר עַל רֹאשׁ הַכְּרוּבִים כְּאֶבֶן סַפִּיר כְּמַרְאֵה דְּמוּת כִּסֵּא.
tĕkhelet is similar to the sea. But the sea is similar to grasses, grasses are similar to the sky, the sky is similar to the Throne of Glory, and the Throne is similar to sapphire, as it is written (Ez. 10:1): “I saw, and here by the spread that was on top of the Cherubim like sapphire stone, the looks of the form of the Throne.”
What is the difference between the enumeration of the Bavli versus Yerushalmi? In terms of content, the Yerushalmi adds grasses, as well as sapphire. In terms of process, we can look at it as follows: In the Bavli, we follow a straight trajectory upward. We go from meditating on the blue thread, to the sea, to the heavens, to the Holy Throne. However, according to the Yerushalmi the trajectory seems to be going one step, lower and more earthy, and then rising one step higher. We go from the blue thread to the sea to the grasses, then we rise up to the heavens to the Holy Throne, and ultimately to the (heavenly) sapphire.
I would like to suggest that מר אמר חדא ומר אמר חדא ולא פליגי
Each one is making a distinct statement, and they do not actually disagree.
The Bavli is referring to the ideal spiritual journey, which hopefully is a continuous upward trajectory. However, the Yerushalmi is referring to the trajectory of the baal teshuva, which has ups and downs. This is represented by going one step lower to meditate on the grasses.
A proof that I might be correct in this interpretation comes from the following teaching in Berachos 34b:
אָמַר רַבִּי אֲבָהוּ: מָקוֹם שֶׁבַּעֲלֵי תְשׁוּבָה עוֹמְדִין — צַדִּיקִים גְּמוּרִים אֵינָם עוֹמְדִין, שֶׁנֶּאֱמַר: ״שָׁלוֹם שָׁלוֹם לָרָחוֹק וְלַקָּרוֹב״. ״לָרָחוֹק״ בְּרֵישָׁא, וַהֲדַר ״לַקָּרוֹב״.
Rabbi Abbahu said: In the place where penitents stand, even the full-fledged righteous do not stand, as it is stated: “Peace, peace upon him who is far and him who is near.” Peace and greeting is extended first to him who is far, the penitent, and only thereafter is peace extended to him who is near, the full-fledged righteous.
Thus, in the Yerushalmi’s version, because it is a baal teshuva, he ascends even higher to that of the heavenly sapphire. (It is notable that Rabbi Avahu was a Palestinian Amora.)