'Refine' in the Bible

And Jehovah saith unto Gideon, 'Yet are the people too many; bring them down unto the water, and I refine it for thee there; and it hath been, he of whom I say unto thee, This doth go with thee -- he doth go with thee; and any of whom I say unto thee, This doth not go with thee -- he doth not go.'

Surely there is for silver a source, And a place for the gold they refine;

When He doth diminish droppings of the waters, They refine rain according to its vapour,

And I turn back My hand upon thee, And I refine as purity thy dross, And I turn aside all thy tin,