When did God make purgatory?

The Catholic Answers

Heaven of course always existed. For where God is, there is heaven. Hell was made when the devil and his followers fell from grace. There was no purgatory for them. Purgatory, then, was made when men began to sin and die with sins repented of, but not fully expiated by the sufferings of this life. Men under the Old Law went to purgatory just as those do who live under the New Law.

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