Zephaniah 3:18 - Clarke's commentary and critical notes on the Bible

I will gather them that are sorrowful for the solemn assembly, who are of thee, to whom the reproach of it was a burden. I will gather - sorrowful - This may refer to those who, during the captivity, mourned for their former religious assemblies; and who were reproached by their enemies, because they could not enjoy their religious solemnities. See Psalms 137:1-9 : "By the rivers of Babylon, there we sat down, yea, we wept, when we remembered Zion. For there they that carried us away captive required of us a song," etc. This very circumstance may be the reference here.