Genesis 42:15-20

ASV_Strongs(i)
  15 H2063 hereby H974 ye shall be proved: H2416 by the life H6547 of Pharaoh H3318 ye shall not go forth H6996 hence, except your youngest H251 brother H935 come hither.
  16 H7971 Send H259 one H3947 of you, and let him fetch H251 your brother, H631 and ye shall be bound, H1697 that your words H974 may be proved, H571 whether there be truth H854 in H3808 you: or else H2416 by the life H6547 of Pharaoh H7270 surely ye are spies.
  17 H622 And he put them all together H4929 into ward H7969 three H3117 days.
  18 H3130 And Joseph H559 said H7992 unto them the third H3117 day, H6213 This do, H2421 and live; H3373 for I fear H430 God:
  19 H3651 if ye be true H259 men, let one H251 of your brethren H631 be bound H1004 in your H4929 prison-house; H3212 but go H935 ye, carry H7668 grain H7459 for the famine H1004 of your houses:
  20 H935 and bring H6996 your youngest H251 brother H1697 unto me; so shall your words H539 be verified, H4191 and ye shall not die. H6213 And they did so.