If a person has to do both the ghusl for removing janaabah and the ghusl for Jumu’ah, it is sufficient for him to do one ghusl for both purposes, and he should intend to do ghusl both to remove janaabah and for Jumu’ah, because the Prophet (peace and blessings of Allaah be upon him) said: “Actions are but by intentions, and each person will have but that which he intended.” Narrated by al-Bukhaari (1) and Muslim (1907).
Al-Nawawi said in al-Majmoo’ (1/368):
If he intended when doing ghusl to do ghusl to remove janaabah and for Jumu’ah, then both are achieved (in one ghusl). This is the correct view. End quote.
Ibn Qudaamah (may Allaah have mercy on him) said:
If he does one ghusl for Jumu’ah and to remove janaabah, and he intends both, that is sufficient, and we do not know of any difference of opinion on this matter. End quote.
Shaykh ‘Abd al-‘Azeez ibn Baaz (may Allah have mercy on him) was asked: Does ghusl to remove janaabah also count for ghusl for Jumu'ah? He replied:
If it is done during the day, that is sufficient for him, but it is better for him to intend both, by intending when doing ghusl that it is for Jumu’ah and for janaabah. Thus he will also attain, in sha Allaah, the virtue of doing ghusl for Jumu’ah too. End quote.
Majmoo’ Fataawa Ibn Baaz (12/406).
Shaykh Ibn ‘Uthaymeen (may Allaah have mercy on him) was asked: What is the ruling on combining ghusl for Jumu’ah and ghusl to remove janaabah? He replied:
There is nothing wrong with that, because if a person is junub and he does ghusl, intending thereby to remove the janaabah and also do ghusl for Jumu’ah, there is nothing wrong with that, just as if a person enters the mosque and prays two rak’ahs intending it to be both the regular Sunnah prayer and greeting the mosque, there is nothing wrong with that.
One of the following scenarios must apply:
1 – He intends to do ghusl to remove janaabah only.
2 – He intends to do ghusl both to remove janaabah and for Jumu’ah.
3 – He intends to do ghusl for Jumu’ah only.
There is a fourth scenario which is unlikely, where he intends neither.
If he intends to do ghusl to remove janaabah, that is sufficient and he does not need to do ghusl for Jumu’ah if it is after sunrise, but if he intends both that is sufficient and he will attain the reward for both. If he intends to do ghusl for Jumu’ah, that is not sufficient and he still has to do ghusl to remove janaabah, because ghusl for jumu’ah is required even when one is not impure but ghusl to remove janaabah is required when one is impure, so it is essential to have the intention of removing this impurity. Some of the scholars said that he should do ghusl twice, but this is not a sound view. End quote.
Majmoo Fataawa Ibn ‘Uthaymeen (16/137).
And Allaah knows best.