Question
Is the perpetrator of major sins punished in the grave if they repent with sincere and truthful repentance?
Answer
I say success: If his repentance is sincere, he will not be punished, with God's permission. Allah, the Exalted, said: "And Allah would not punish them while they seek forgiveness" and He said: "Repent to Allah with sincere repentance; perhaps your Lord will remove from you your misdeeds." Here, "perhaps" is for confirmation, and Allah knows best.