Everything that the Prophet told is true and right, whether it is among the issues of halal or haram, the stories of the prophets, or matters that will happen in the future during this life and in the Hereafter.  

Among the matters that the Prophet informed about are: the torture in the grave and the enjoyment therein, and the questioning by the two angels: Munkar and Nakir.  

The torture in the grave: It is obligatory to believe that Allah tortures all the accountable blasphemers in their graves. Allah orders the harmful insects of the Earth to eat their bodies. Also, He orders the Earth to close in on them. Other types of torture will also be inflicted on them. Their graves will become like ditches of Hell. On the other hand, the Muslims who are major sinners, and died without repenting are of two groups:  

Those tortured in their graves. 

Others forgiven by Allah from being tortured therein.