Deuteronomy 21:9

So shalt thou put away Heb. and thou, thou shalt put away, an emphatic variation of the formula with which D usually closes similar laws (see Deuteronomy 13:5, (6), Deuteronomy 19:13, etc.), as if he only now resumed his own words.

when thou shalt do, etc.] To make the construction right we should prefix to this clause, the words that it may be well with thee. See Deuteronomy 6:18.