Hesabu 31 : 23 Numbers chapter 31 verse 23

kila kitu kiwezacho kuuhimili moto, mtakipitisha katika moto, nacho kitakuwa safi, pamoja na haya kitatakaswa kwa hayo maji ya farakano; na kila kitu kisichouhimili moto mtakipitisha katika hayo maji.
soma Mlango wa 31

everything that may abide the fire, you shall make to go through the fire, and it shall be clean; nevertheless it shall be purified with the water for impurity: and all that doesn't withstand the fire you shall make to go through the water.