Iqāmu's-ṣalāt is interpreted in two senses:
1. The phrase aqāmu's-ṣalāt is used in the sense of verbal affirmation lacking actual confirmation; as in the following verses:
So when you meet those who associate partners with Allah, kill them wherever you find them... But if they turn back {that is, if they turn away from shirk (associating partners with God)} and establish ṣalāt (iqāmu's-ṣalāt) and give zakāt {that is, if they affirm the establishment of ṣalāt and the giving of zakāt}, then let them go their way. (al-Tawba 9:5)
They do not observe any pact regarding a believer. Those are the transgressors. But if they repent, establish ṣalāt (iqāmu's-ṣalāt), and give zakāt {that is, if they affirm the establishment of ṣalāt and the giving of zakāt}, then they are your brothers in religion. (al-Tawba 9:10-11)
A similar usage is found in Sūrat al-Sajda.
2. The phrase iqāmu's-ṣalāt is used in the sense of performing it—i.e., the prayer—fully and without deficiency; as in the following verses:
And We made them leaders guiding by Our command. And We inspired to them the doing of good deeds, establishment of ṣalāt (iqāmu's-ṣalāt) {that is, performing the prayer fully and without deficiency}, and giving of zakāt {that is, giving the obligatory zakāt}... (al-Anbiyāʾ 21:73)
A similar usage is found in Sūrat al-Muzzammil.
Those who believe in the unseen ({in the Qur'an, in its being sent down from Allah to Muhammad}), establish ṣalāt (iqāmu's-ṣalāt) {that is, perform the prayer fully and without deficiency}, and spend out of what We have provided for them {that is, give zakāt}. (al-Baqara 2:3)