Let us strike an example with the prayer, and measure by it the rest of the outward acts of worship:

The people of Oneness (Ahl al-Tawhid) have established that the prayer is the Commander of the Faithful, and in another aspect, it is his Veil (Hijab) and his Greatest Name. From this, the expert gnostic deduces that their manifestation to people is the prayer, because it is a connection (silah) between the servant and his Lord, a mercy for the believers, and a proof against the disbelievers. The multiplicity of their manifestations—meaning the Meaning (Ma'na) and the Name (Ism)—is in correspondence to the repetition of prayer in the Wise Remembrance, according to the saying of the Exalted: {Establish prayer at the decline of the sun [from its meridian] until the darkness of the night and [also] the Quran of dawn. Indeed, the recitation of dawn is ever witnessed} (Al-Isra 78).

And the saying of the Glorified: {And from [part of] the night, pray with it as additional [worship] for you; it is expected that your Lord will resurrect you to a praised station} (Al-Isra 79).

And His saying: {Maintain with care the [obligatory] prayers and [in particular] the middle prayer and stand before Allah, devoutly obedient} (Al-Baqarah 238).