It will increase one’s khushu to think of how the Salaf were when they prayed, and motivate one to follow their example. “If you were to see one of them when he stood up to pray and started reciting the words of his Master, it would cross his mind that he was standing before the Lord of the Worlds, so he would be filled with overwhelming awe.” (Al-Khushoo’ fi’l-Salaah by Ibn Rajab, p. 22).
Mujaahid, may Allah have mercy on him, said: “When one of them stood in prayer, he would be too fearful of his Lord to allow his eyes to be drawn to anything, or to turn aside or to fidget by playing with pebbles or anything else or to think of any worldly matter, unless he forgot, during prayer.” (Ta’zeem Qadr al-Salaah, 1/188)
When Ibn al-Zubayr, may Allah be pleased with him, stood up to pray, he would be like a stick (i.e., immobile) with khushu. Once he was prostrating when a missile from a catapult was launched at him, when Makkah was being besieged, and part of his garment was torn away whilst he was praying, and he did not even raise his head. Muslimah ibn Bashshaar was praying in the mosque when part of it collapsed, and the people got up [and fled], but he was praying and did not even notice. We have heard that one of them was like a garment thrown on the floor; one of them would end his prayer with the colour of his complexion changed because he had been standing before Allah. One of them would not know who was standing to his right or left when he prayed. One of them would go pale when he did wudu for prayer, and it was said to him, “We see that when you do wudu a change comes over you.” He said, “I know before Whom I am going to stand.” When the time for prayer came, ‘Ali ibn Abi Taalib would be visibly shaken, and the colour of his face would change. It was said to him, “What is the matter with you?’ He said, “By Allah, there has come the time of the amaanah (trust) which Allah offered to the heavens and the earth, and the mountains, but they declined to bear it and were afraid of it, but I bore it [cf. Al-Ahzaab 33:72].”
When Sa’eed al-Tanookhi prayed, there would be tears rolling down his cheeks onto his beard. We heard that one of the Taabi’een, when he stood up to pray, his colour would change, and he would say, “Do you know before Whom I am going to stand and with Whom I am going to talk?” Who among you has fear and respect like this? (Silaah al-Yaqazaan li Tard al-Shaytan, ‘Abd al-‘Azeez Sultaan, p. 209)
They said to ‘Aamir ibn ‘Abd al-Qays, “Do you think to yourself during prayer?” He said, “Is there anything I like to think about more than the prayer?” They said, “We think to ourselves during prayer.” He said, “About Paradise and al-hur (“houris”) and so on?” They said, “No; about our families and our wealth.” He said, “If I were to be run through with spears, it would be dearer to me than thinking to myself about worldly matters during prayer.”
Sa’d ibn Mu’aadh, may Allah be pleased with him, said: “I have three qualities, which I wish I could keep up all the time, then I would really be something. When I am praying, I do not think about anything except the prayer I am doing; if I hear any hadith from the Messenger of Allah, peace and blessings of Allah be upon him, I do not have any doubts about it; and when I attend a janaazah (funeral), I do not think about anything except what the janaazah says and what is said to it.” (Al-Fataawa li Ibn Taymiyah, 22/605).
Haatim, may Allah have mercy on him, said: “I carry out what I am commanded; I walk with fear of Allah in my heart; I start with the [correct] intention; I magnify and glorify Allah; I recite at a slow and measured pace, thinking about the meaning; I bow with khushu; I prostrate with humility; I sit and recite the complete tashahhud; I say salaam with the [correct] intention; I finish with sincerity towards Allah; and I come back fearing lest [my prayer] has not been accepted from me, so I continue to strive until I die.” (Al-Khushoo’ fi’l-Salaah, 27-28).
Abu Bakr al-Subghi said: “I lived through the time of two imaams (leaders) although I was not fortunate enough to hear them in person: Abu Haatim al-Raazi and Muhammad ibn Nasr al-Marwazi. As for Ibn Nasr, I do not know of any prayer better than his. I heard that a hornet stung him on his forehead and blood started flowing down his face, but he did not move.” Muhammad ibn Ya’qoob al-Akhram said: “I have never seen any prayer better than that of Muhammad ibn Nasr. Flies used to land on his ears, and he did not shoo them away. We used to marvel at how good his prayer and khushu were. His fear [of Allah] in prayer was so great that he would put his chin on his chest as if he were a piece of wood standing up.” (Ta’zeem Qadr al-Salaah, 1/58). Shaykh al-Islam Ibn Taymiyah, may Allah have mercy on him, when he started to pray, used to tremble so much that he would lean right and left. (Al-Kawaakib al-Durriyah fi Manaaqib al-Mujtahid Ibn Taymiyah, by Mar’i al-Karami, p. 83).
Compare this with what some of us do nowadays, looking at our watches, adjusting our clothes, fiddling with our noses, thinking of deals and counting our money whilst praying, or tracing the patterns of decorations on carpets and ceilings, or trying to see who is beside us. Think of how anyone would behave before some great leader of this world – would they dare to behave in such a manner then?!