I would like to ask if its okay to pay for the youtube premium and if i pay for others too will i be responsible for what they watch / hear?
All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
There is nothing wrong with subscribing to YouTube to watch permissible and beneficial content, and the same goes for paying the subscription for others who are not likely to watch impermissible content; even if they happen to do so, they bear the sin for it. Allah, The Exalted, Says (what means): {And every soul earns not [blame] except against itself, and no bearer of burdens will bear the burden of another. Then to your Lord is your return, and He will inform you concerning that over which you used to differ.} [Quran 6:164]
As for those whom you know or predominantly believe that they would most likely watch prohibited content, it is impermissible for you to help them in this regard. Allah, The Exalted, Says (what means): {And cooperate in righteousness and piety, but do not cooperate in sin and aggression. And fear Allah; indeed, Allah is severe in penalty.} [Quran 5:2]
Allah knows best.
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