How can one combine the intention of four rak'ahs before Dhuhr from the twelve supererogatory rak'ahs with the intention of the four rak'ahs mentioned in the Prophet's hadith, and should one pray eight rak'ahs before Dhuhr and six after it, or should the intention be divided?

Several Hadiths have been narrated regarding the virtue of praying four rak'ahs before Dhuhr, among them: "Whoever observes four rak'ahs before Dhuhr and four after it, Allah, the Mighty and Majestic, will forbid his flesh from the Fire." These four are the regular Sunnah prayers (ratibah) before Dhuhr, of which two rak'ahs are emphasized (mu'akkadah) and two are not emphasized. It is sufficient for a Muslim to pray four rak'ahs before Dhuhr with the intention of the ratibah prayer to attain the virtue mentioned in the Hadith, and not to pray eight rak'ahs.