Should she testify to something that she has not been asked for but that may benefit the person against whom she is testifying?

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Should he give testimony against a Muslim who wronged a Christian and took his wealth unlawfully, or should he conceal his wrongdoing?
He is outwardly Muslim but he rarely attends the mosque; should we think badly of him?

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Related Answers:
He gave false witness – what should he do?
Why is the witness of one man considered to be equal to the witness of two women?
Is the testimony of a person who raises pigeons acceptable?
Should he give testimony against a Muslim who wronged a Christian and took his wealth unlawfully, or should he conceal his wrongdoing?
He is outwardly Muslim but he rarely attends the mosque; should we think badly of him?

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