What is the ruling on a wife taking money from her husband's wealth without his knowledge, given that he had previously given her permission to do so?

As long as the husband has pardoned his wife for what she took from his money previously without his knowledge, and has given her permission to take from it later without his knowledge, then there is no sin upon her. However, it is advisable not to excessively take without his knowledge, lest it lead to his ill-will, which would have undesirable consequences.