Is a slave's testimony accepted regarding his master's marriage or an affirmation of divorce concerning the master's female slave?

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A slave's testimony is not accepted concerning his master's marriage, nor for his master regarding the divorce of the master's female slave. This is because affirming the divorce results in the liberation of the female slave and permits the master access to her private parts. Similarly, a slave's marriage benefits the master, and benefiting a person's property benefits that person.