He who sees the Passageway of the Sea (i.e., the place where Bnei Yisrael crossed the Red Sea) and the Passageway of the Jordan (where they entered Eretz Yisrael) ... All who see them should give praise and thanks to Hashem. Ein Ayah:
Among people who see places connected to miracles, there are some who appreciate the miracles and react emotionally upon seeing the places where Hashem did great things. Even those who lack a full understanding of miracles, in general, have some light shine in their spirits when they are exposed to places where wondrous miracles happened that caused a great deal of light to shine on the world. That is the reason that the gemara stresses that everyone should make a blessing in the special places mentioned.
The beracha focuses not only on the direct benefit that the miracles caused, but also on the resulting recognition of the Divine glory. The gemara mentions two elements of our reaction: giving praise and thanking Hashem. There were boundless positive results, both physical and spiritual, that were achieved by means of the miracles that affected Klal Yisrael, which includes every individual within it. Corresponding to this, we are required to give specific thanks. While Bnei Yisrael should give specific thanks for their special, more direct part in that good, the praise also relates to the benefit to the whole world from Bnei Yisrael’s spiritual benefit. The Reason for The Miracles
(condensed from Ein Ayah, Berachot 9:5) Gemara:
The Passageway of the Sea is understandable as it says, "Bnei Yisrael came into the midst of the sea in dry land" (Shemot 14:22), as is the Passageway of the Jordan, as it is written, "... and all of Israel passed through it in dry land" (Yehoshua 3:17). Ein Ayah:
The language of this gemara fits in well with the thesis of the Rambam (Yesodei Hatorah 8:1). He said that the main purpose of the miracle of the splitting of the sea was not to prove the reliability of Moshe, for this was to be accomplished clearly at the giving of the Torah at Sinai. There it says, "... and in you [Moshe] they will believe forever" (Shemot 19:9). Rather, the main purpose was to enable Bnei Yisrael to pass the Sea, the Jordan, and the Arnon Valley, respectively. In order to stress this, the Rabbis refer to each one as "the Passageway."
On the other hand, presumably, even the Rambam would agree that the reason that they were in the position that the miracles became necessary was for the spiritual gain of heightened belief in Hashem and fear of Him. Even if the Rambam did not think that this was the main factor, it certainly was a factor.