Does divorce occur by saying "think about separation" four times as a threat, before consummating the marriage with the wife?

Divorce does not occur except with an explicit pronouncement, or an implicit one (which is any word that indicates separation but is not explicit in doing so), and an implicit pronouncement does not constitute divorce unless there is an intention to enact it. Your command to your wife to think about divorce does not indicate separation, and your wife remains under your marital bond as she was.