Jeremiah 34:7-11

ASV_Strongs(i)
  7 H4428 when the king H894 of Babylon's H2428 army H3898 was fighting H3389 against Jerusalem, H5892 and against all the cities H3063 of Judah H3498 that were left, H3923 against Lachish H5825 and against Azekah; H7604 for these alone remained H5892 of the cities H3063 of Judah H4013 as fortified H5892 cities.
  8 H1697 The word H3414 that came unto Jeremiah H3068 from Jehovah, H310 after H4428 that the king H6667 Zedekiah H3772 had made H1285 a covenant H5971 with all the people H3389 that were at Jerusalem, H7121 to proclaim H1865 liberty unto them;
  9 H376 that every man H5650 should let his man-servant, H376 and every man H8198 his maid-servant, H5680 that is a Hebrew H5680 or a Hebrewess, H7971 go H2670 free; H5647 that none should make bondmen H3064 of them, to wit, of a Jew H251 his brother.
  10 H8269 And all the princes H5971 and all the people H935 obeyed, that had entered H1285 into the covenant, H376 that every one H5650 should let his man-servant, H376 and every one H8198 his maid-servant, H7971 go H2670 free, H5647 that none should make bondmen H8085 of them any more; they obeyed, H7971 and let them go:
  11 H310 but afterwards H7725 they turned, H5650 and caused the servants H8198 and the handmaids, H7971 whom they had let go H2670 free, H7725 to return, H3533 and brought them into subjection H5650 for servants H8198 and for handmaids.