Developing Khushu in the prayer By Muhammed Salih al Munajjid
Salaah is the greatest of the practical of Islaam, and khushoo in prayer is required by Shareeah. One of Shaytaan's (Saytan) most significant plots become to divert people from Salaah by all possible means and to whisper to them during their prayer so as to deprive them of the joy of this worship and cause them to lose the reward for it. As khushoo will be the first thing to disappear from the earth, and we are living in the last times, the words of Hudhayfah (radiy Allaah anhu) are particularly to us. The fist thing of your religion that you will lose is Khushoo, and last thing that you will lose of your religion is Salaah.
There may be a person praying who has no goodness in him, and soon you will enter the mosque and not finding anyone who has Khushoo. Because of what every person knows about himself, and because of the complaints that one hear from many people about waswaas (insinuating thoughts from Shaytaan) during the Salaah and loss of khushoo, the need for some discussion of this mater is quite obvious. From the Author's Introduction.