Sami'allaahu liman hamidah, Rabbanaa wa lakal-hamd (Allah hears whoever praises Him. Our Lord, praise is Yours). Every Muslim knows this dua by heart as it is recited in the five daily salahs upon rising from the rukoo. Reciting this dua upon rising from the rukoo is a wajib, must, component of salah. Forgoing this step knowingly will make your salah incomplete. Apart from being essential to the completion of Salah, this dua is a preamble, a beautiful way to gain Allah's attention. The believer seeks to divert Allah's attention towards them by stating that Allah hears whoever praises HIM. O Lord, all praises are yours; look upon me as I kneel and prostrate in prayer and answer my prayers.
The dua for upon rising from the rukoo has been reiterated time and again by the Prophet Muhammad(ﷺ) as found in various hadith. The dua voices the glory of Allah (سُبْحَانَهُ وَتَعَالَى) and declares that all praises and good words are for Him (Sahih al-Bukhari 799). The same has been reported in (Sunan an-Nasa'i 931), where the Prophet Muhammad (ﷺ) told a sahabi who recited the second part of this dua that this dua is so pleasing to Allah that 30-odd angels hastened to write down the man's good deeds in an attempt to be the first. The same has been reported in ( Sunan an-Nasa'i 1062).
Prayer Duas
Sami'allaahu liman hamidah.
Allah hears whoever praises Him.
Rabbanaa wa lakal-hamd, hamdan i katheeran tayyiban mubaarakanfeeh.
Our Lord, praise is Yours, abundant, good and blessed praise.
Mil'as-samaawaati wa mil 'al-'ardhi wa maa baynahumaa, wa mil 'a maa shi'ta min shay 'in ba'd. 'Ahlath-thanaa'i walmajdi, 'ahaqqu maa qaalal-'abdu, wa kullunaa laka 'abdun. Allaahumma laa maani'a limaa 'a'tayta, wa laa mu'tiya limaa mana'ta, wa laa yanfa'uthal-jaddi minkal-jadd.
(A praise that) fills the heavens and the earth and what lies between them, and whatever else You please. (You Allah) are most worthy of praise and majesty, and what the slave has said, we are all Your slaves. O Allah, there is none who can withhold what You give, and none may give what You have withheld. And the might of the mighty person cannot benefit him against You.
Prayer (salah) requires great concentration and attention on the believer's part. Therefore, the dua to be recited upon rising from the rukoo should be recited with utmost concentration and wholeheartedness. Secondly, the believer must believe that Allah Azzawajal is listening to their prayer and will make it come true if it is beneficial for them.
The single most important benefit of the dua upon rising from the rukoo is proclaiming the greatness of Allah (سُبْحَانَهُ وَتَعَالَى). Thus, the Almighty hears the person who praises Him. Thereby, this dua serves as a prerequisite for the many wishes of a believer being fulfilled by Allah (سُبْحَانَهُ وَتَعَالَى) and him being showered by the blessings of Allah (سُبْحَانَهُ وَتَعَالَى). The recitation of this dua also increases one's good deeds multifold in addition to the forgiveness of one's sins.