There is no doubt that talking to Allah, humbling oneself before Him, asking things from Him and earnestly seeking His help, all help to strengthen the slave’s ties to his Lord and increase his khushu. Du’a is an act of worship, and we are commanded to make du’a. Allah says:
“… call upon Him in humility and in secret…” (Surah al-An’aam 6:63).
The Prophet , peace and blessings of Allah be upon him, said:
“Whoever does not call on Allah, Allah will be angry with him.” (Reported by al-Tirmidhi, Kitaab al-Da’waat, 1/426)
It was reported that the Prophet, peace and blessings of Allah be upon him, used to make du’a at specific places in the prayer, i.e., in sujud, between the two prostrations and after the Tashahhud. The greatest of these is in sujud, because the Prophet, peace and blessings of Allah be upon him, said:
“The closest that the slave can be to his Lord is when he is prostrating, so increase your du’a [at that time].” (Reported by Muslim, Kitaab al-Salaah, Baab maa yuqaalu fi’l-rukoo’ wa’l-sujood. No. 215).
And he, peace and blessing of Allah be upon him said:
“… As for sujud, strive hard to make du’a in it, for it is bound to be answered for you.” (Reported by Muslim, Kitaab al-Salaah, Baab al-Nahy ‘an qiraa’at al-Qur’an fi’l rukoo’ wa’l-sujood, no. 207).
One of the du’as which the Prophet, peace and blessings of Allah be upon him, used to recite in his sujud was:
“Allaahumma’ghfir li dhanbi diqqahu wa jillahu wa awwalahu wa aakhirahu wa ‘alaaniyatahu wa sirrahu (O Allah, forgive me my sins, the minor and the major, the first and the last, the open and the hidden).” (Reported by Muslim, Kitaab al-Salaah, Baab ma yuqaalu fi’l-rukoo’ wa’l-sujood, no. 216).
He also used to say:
“Allaahumma’ghfir li maa asrartu wa maa a’lantu (O Allah, forgive me what I have done in secret and done openly).” (Reported by al-Nisaa’i, al-Mujtabaa, 2/569).
One of the things that he, peace and blessings of Allah be upon him, used to recite after the Tashahhud is what we learn from the hadith:
“Allahumma innii a ‘uudhu bika min ‘adhaabi-qabri, wa min ‘adhaabi jahannama, wa min fitnatil-mahya wal mamati wa min sharri fitnatil masihid dajjal. (O Allah, I seek refuge in You from the punishment of the grave, and from the punishment of the Hell-fire and from the trials of life and death, and from the evil of the trial of the False Messiah).” (Recorded in Al- Bukhari 2/102, Muslim 1/412)
He, peace be upon him, also used to say,
“Allaahumma innee a’oodhu bika min sharri maa ‘amiltu wa min sharri maa lam a’mal (O Allah, I seek refuge with You from the evil of what I have done and the evil of what I have not done).” (Recorded in Muslim)
He taught Abu Bakr al-Siddeeq, may Allah be pleased with him to say:
“Allaahumma innee zalamtu nafsi zulman katheeran, wa la yaghfir al-dhunooba illa anta, faghfir li maghfiratan min ‘indaka warhamni innaka anta al-Ghafoor al-Raheem (O Allah, I have wronged myself very much, and no one can forgive sin but You. Grant me forgiveness from You and have mercy on me, for You are the All-Forgiving, Most Merciful).” (Recorded in al Bukhari 8/388)
He heard a man saying in his Tashahhud: “Allaahumma inne as’aluka yaa Allah al-Ahad al-Samad alladhi lam yalid wa lam yoolad wa lam yakum lahu kufuwan ahad an taghfir li dhunoobi innaka anta’l-Ghafoor al-Raheem (O Allah, I ask You O Allah, the One, the Self-Sufficient Master, Who begets not neither is begotten, and there is none like unto Him, to forgive me my sins, for You are the All-Forgiving, Most Merciful).” He (peace and blessings of Allah be upon him) said to his companions: “He has been forgiven, he has been forgiven.” (Recorded in Abu Dawud)
He heard another man saying, “Allaahumma innee as’aluka bi-anna laka’l-hamd, laa ilaaha ill anta wahdaka laa shareeka lak al-Mannaan yaa badee’ al-samawaati wa’l-ard, yaa dhaa’l-jalaali wa’l-ikraam, ya hayyu yaa qayyoom, innee as’aluka al-jannah wa a’oodhu bika min al-naar (O Allah, I ask You as all praise is due to You, there is no god but You Alone, with no partner or associate, the Bestower, O Originator of the heavens and earth, O Possessor of Glory and Honour, O Ever-Living, O Self-Sustaining, I ask You for Paradise and I seek refuge with You from Hell).” The Prophet, peace and blessings of Allah be upon him, said to his companions: “Do you know by what did he ask Allah?” They said, “Allah and His Messenger know best.” He said, “By the One in Whose hand is my soul, he asked Allah by His Greatest Name (ismuhu’l-a’zam) which, when He is called by it, He responds, and if He is asked by it, He gives.” (Recorded in Abu Dawud)
The last thing he, peace be upon him, would say between the Tashahhud and the Tasleem was: “Allaahumma’aghfir li maa qaddamtu wa ma akhkhartu wa maa asrartu wa maa a’lantu wa maa asraftu wa maa anta a’lam bihi minni anta’l-muqaddim wa anta’l-mu’akhkhir, laa ilaaha illa anta (O Allah, forgive me what I have done in the past, and what I will do in the future, and what I have concealed, and what I have done openly, and what I have exceeded in, whatever You know about more than I. You are the Bringer-Forward, and You are the Delayer, there is no god except You).” (Recorded in Sifat al-Salah p163)
Memorising du’as like these will solve the problem that some people have of remaining silent behind the imaam when they have finished the Tashahhud because they do not know what they should say.