Istinjaa' does not require intention and obligatory Ghusl needs different intention
19-3-2012 | IslamWeb
Question:
Assalamu alaykum, when you have to do ghusl and before that you go to toilet. is it allowed to do ghusl without making istinja before? Is istinja included in ghusl or do i need a special intention for istinja? Jazakumullahu khayran.
Answer:
All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
According to the view of the majority of the scholars 
Istinjaa' (which is to remove what comes out of the two private parts from the place where it comes out or the place that is nearest to it, whether by washing or by wiping it with stones and the like) does not need an intention. An-Nawawi, 
said in his book entitled Al-Majmoo’, “Removing the impurity does not need intention; this is the correct and well-known opinion which the majority of the scholars authoritatively asserted. Besides,The author of Al-Haawi and Al-Baghawi reported the consensus of the scholars on this issue in Sharh As-Sunnah.”
Moreover, Al-Hattab from the Maaliki school of jurisprudence, said, “It is not a condition to have intention for removing the impurity; this is the known opinion, however Al-Qaraafi reported that it needs intention and this is a Dha’eef [weak] narration. Rather, Ibn Basheer and Ibn ‘Abdus-Salaam reported an agreement of the scholars that it does not need intention.”
Therefore, if the place is cleaned from the impurity during Ghusl (ritual bath) then this suffices from performing Istinjaa.
However, if the Ghusl is obligatory due to sexual defilement and one had impurity on his body, then is purity achieved by performing one Ghusl for removing the state of sexual defilement and for removing the impurity (on his body)? The scholars differed in opinion about this, some of them said that it is sufficient and it removes the state of sexual defilement and that if an impurity remains on part of the body it does not prevent from removing the state of sexual defilement. For instance, if he washes his nose or his hands in ablution and impurity remained on his nose for example, then his ablution is still correct. This is the view of the Hanbali school. However, some jurists said that it is not sufficient and some of them said that it is sufficient if the impurity is removed and if it is not thick in a way that it prevents the water reaching the part of the body. However, it is better in order to be on the safe side to wash the place of impurity first and then perform the obligatory Ghusl.
It should be noted that the obligatory Ghusl needs a special intention. Ibn Qudaamah said in his book entitled Al-Mughni, “Intention is a condition for purity from all kinds of impurities, and ablution, or Ghusl, or Tayammum (dry ablution) are not valid unless one has made it [intention]. This is reported from ‘Ali 
and Rabee’ah, Maalik, Ash-Shaafi’i, Al-Layth, Ishaaq, Abu ‘Ubaydah, Ibn Al-Munthir…said this.”
For more benefit, please refer to Fataawa 174511, 173131 and 170735.
And Allaah Knows best.