The Fast of Ab is the saddest day on the Jewish calendar, when we commemorate the destruction of the Temple in Jerusalem, the exile of the Jewish people, and numerous massacres. Starting on the evening before, for a 24 hour period, we do not eat or drink, deprive ourselves from any physical pleasure, we do not wear leather shoes, and take no baths. For most of the day (until the afternoon), we do not even great each other, as a sign of deep morning. Instead of a greeting, we tell each other "Murir Habemos" ('We Shall Die'). Remarkably, the tunes that are sung in the Spanish-and Portuguese Jewish community during this day are among the oldest music in our liturgy, some even from the 16th Century. And they are also among the most beautiful melodies. The very first that is sung by the cantor during the evening service is Psalm 137, known as "By the Rivers of Babylon".
1 By the rivers of Babylon, there we sat down, even did we weep, when we remembered Zion. 2 We hung up our harps on the willows there. 3 For there, those that carried us away in captivity, required of us a song. 4 How shall we sing the Lord’s song on strange soil? 5 If I forget you, O Jerusalem, let my right hand forget (me). 6 If I do not remember you, let my tongue cleave to the roof of my mouth; If I prefer not Jerusalem above my highest joy. 7 Remember, O Lord, the children of Edom on the day of Jerusalem; Those who said: Raze it! Raze it to its foundation! 8 O daughter of Babylon, who is to be destroyed; happy shall he be who pays you back for what you have done to us. 9 Happy shall he be, that takes and dashes your little ones against the rock.