From Psalm 137 - If I forget thee, o Jerusalem
Im Eshkachech is sung at a wedding, even though it has a wistful sadness to it. This is to show how, even in our moment of joy, we are mindful that the Temple at Jerusalem remains unfulfilled, and the world unperfected.
In this section: Am Yisrael Chai --- Nachamu Ami --- Im Eshkachech