Ruling on combining multiple intentions for a single act of worship
12-1-2014 | IslamWeb
Question:
Is it permissible for me to perform a single prayer with more than one intention? For example, may I join the intentions for performing Istikhaarah (i.e. guidance-seeking prayer) and a Sunnah prayer in the same prayer?
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.
There is no harm in combining two intentions for a single act of worship as long as they are overlapped such as the Friday Ghusl and the Ghusl of Janabaah (i.e. ritual bath of purification from post sexual intercourse impurity). Another example would be joining a specific voluntary prayer such as that of Tahiyyatul-Masjid (i.e. salutation to the mosque) with a voluntary or obligatory prayer.
It is not valid to combine the intention to observe two independent acts of worship while each of which is required to be done individually and neither of which can be included within the other. For example, the Maghrib prayer may not be combined with a recommended voluntary prayer as a single act of worship with the same intention. This is invalid since these two acts of worship cannot be considered parts of one another.
Hence, there is no harm in combining the intentions to observe the prayer of Tahiyyatul-Masjid and an obligatory or voluntary act of worship in the same prayer. The same ruling applies to joining the Istikhaarah (i.e. guidance-seeking prayer) with another voluntary prayer. However, other obligatory and recommended voluntary acts of worship may not be combined because neither of them can take the place of the other.
An-Nawawi 
said in Al-Athkaar, "If one recited the supplication of Istikhaarah after the Sunnah of the Thuhr prayer or any recommended voluntary prayer, general or specific (i.e. reported Rawaatib or Sunnah prayers that have a specific order, number, and so on), it would suffice." [Fat-h Al-Baari]