What is the punishment for one who knows a ruling and deliberately errs in it?

One who is asked about a Sharia matter and knows its ruling must explain it and not conceal it, otherwise, they expose themselves to damnation and expulsion from God's mercy, as stated in His Almighty saying: "Indeed, those who conceal what We sent down of clear proofs and guidance after We made it clear for the people in the Scripture – those are cursed by Allah and cursed by those who curse." This verse is general for anyone who conceals knowledge from God's religion that needs to be disseminated, especially if they are asked about it.

As for one who knows and issues a fatwa contrary to that, their sin is greater for two reasons: firstly, they concealed what they were asked about, and secondly, they slandered God with falsehood by saying what God has not authorized, as per His Almighty saying: "And do not say about what your tongues assert falsely, 'This is lawful and this is forbidden,' to invent a falsehood against Allah. Indeed, those who invent a falsehood against Allah will not succeed."