Rabbi Roodyn

ג) זָכַר חַסְדּוֹ וֶאֶמוּנָתוֹ לְבֵית יִשְׂרָאֵל רָאוּ כָל אַפְסֵי אָרֶץ אֵת יְשׁוּעַת אֱלֹקֵינוּ

He remembered His kindness and His faith to the house of Israel; all the ends of the earth have seen the salvation of our God.

The Radak explains that this pasuk refers to the chessed and the emunah that Hashem had for the Jewish people when He took us out of exile in full view of the nations of the world, even though who live at the remote areas at the ends of the earth, the afsei aretz.

The Seforno explains that the chessed is also a reference to the chessed that the Jewish people demonstrated when they followed the Divine presence into the great unknown with the exodus from Egypt. No good action goes unrewarded and Hashem repays us for that chessed by performing the ultimate chessed in redeeming us from exile. In this vein emunah is a reference to Hashem recalling the covenant that He made with our forefathers.