ANSWER:

You should tell him or send him a video or text from an authentic scholar stating that masturbation is haram and he cannot pray without doing ghusl. His prayer is invalid!

Kindly refer to the following link(s):

https://youtu.be/HY7t91VCAfQ

https://islamqa.info/en/89935

How should I deal with brother who masturbates and then prays salaah without performing fardh ghusl, he is in the state of janaabah a lot of the time. Please Answer as soon as possible

Masturbation | December 12, 2017 4:27 pm
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Some scholars said that one can masturbate if there is fear of fornication.My question is can I masturbate if I have a high desires and feeling very bad and my country is full of beautiful girls, and it will take many many years for me to finish my studies and get a job, and then get married.Please clarify !
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If husband put his finger inside wife’s private part and wife put her finger in her private part (genital)and stimulate it as a part of enjoyment, would it be haram? Please clarify this.