Allah T'ala says in the Holy Quran:
During the centuries of the crusades, all sorts of slanders were invented against Prophet Muhammad (pbuh). But with the birth of the modern age, marked with religious tolerance and freedom of thought, there has been a great change in the approach of Western authors in their delineation of his life and character. The views of some non-Muslim scholars regarding Prophet Muhammad, given at the end, justify this opinion.
But the West has still to go a step forward to discover the greatest reality about Muhammad and that is his being the true and the last Prophet of God for the whole humanity. In spite of all its objectivity and enlightenment there has been no sincere and objective attempt by the West to understand the Prophethood of Muhammad (pbuh). It is so strange that very glowing tributes are paid to him for his integrity and achievement but his claim of being the Prophet of God has been rejected explicitly or implicitly. It is here that a searching of the heart is required, and a review of the so-called objectivity is needed. The following glaring facts from the life of Muhammad (pbuh) have been furnished to facilitate an unbiased, logical and objective decision regarding his Prophethood.Read more...
Advice of Hadhrat Sheikh
Eighth Discourse from Al-Fath ar-Rabbani
Hadhrat Sheikh Abdul Qadir Jeelani (RA)
The pious pretender [mura'i] wears clean clothes, but his heart is filthy. He abstains from permissible things, and is too lazy to earn a livelihood. He eats off his religion, and exercises no self-restraint at all. He consumes things that are explicitly forbidden [haram]. His game may be hidden from the common folk ['awamm], but it is not concealed from the Elite [khawass]. His asceticism [zuhd] and obedient worship [ta'a] are all superficial. His external facade is splendidly fashioned, but his interior is a ruin.
Woe unto you! Obedient service to Allah (Almighty and Glorious is He) is performed by the heart [qalb], not the outer mold [qalab]. All these things are connected with hearts, innermost beings and spiritual qualities [ma'ani]. Strip yourself bare of what you now have on, so that I may get for you from the Lord of Truth (Almighty and Glorious is He) an outfit that will never wear out. Get undressed so that He may clothe you. Take off the garment of your indifference to the rights [huquq] of Allah (Almighty and Glorious is He). Take off the garment of your attachment to creatures and your idolization [shirk] of them. Take off the garment of lust, frivolity, conceit and hypocrisy, of your love of being acceptable to people and having them approach you and bring you gifts. Take off the clothing of this world, and put on the clothing of the hereafter. Divest yourself of your power, your strength and your very existence [wujud], and throw yourself down before the Lord of Truth (Almighty and Glorious is He) without power, without strength, without attachment to material means [sabab], and without idolatrous worship of any created thing. Then, if you do this, you will see His gracious favors all around you. His mercy will come to join you, and His blessing and benefit will clothe you and enfold you in their embrace. Flee to Him. Dedicate yourself wholly to Him, naked, with no you and no one other than you. Move toward Him in isolation, distinct from any other than Him. Move toward Him separately, apart, until He joins and connects you to your inner and outer forces [quwa zahirika wa-batinika]. Even if He were to close the whole universe [al-akwan] against you, and make you carry all its burdens, this would do you no harm; not at all, for He would protect you throughout.
When someone blots out creatures by virtue of his realization of Unity [tawhid], blots out this world by virtue of his renunciation [zuhd], and blots out everything else apart from his Lord (Almighty and Glorious is He) by virtue of his longing, that person is completely prepared for righteousness [salah] and success [najah], and he will enjoy the all the blessings of this world and the hereafter. You must experience the mortification of your lower selves, your desires and your devils, before you die. Experience the special death [al-mawt al-khass] before the common death [al-mawt al-'amm].
O my people! Respond to me, for I am the crier of Allah (Almighty and Glorious is He), calling you to His door and His obedient service. I am not calling you to myself. The hypocrite does not call the people to Allah (Almighty and Glorious is He); he is a self-promoter. He is looking for favors and acceptance, seeking worldly gain.
O ignorant one, you give up listening to words like these, and sit there in your cell, with only your own self and your passions for company! What you need first is the fellowship of the Shaikhs [shuyukh], and the slaying of the lower self, the natural instincts and everything apart from the Master (Almighty and Glorious is He). You must stay by the door of their houses, I mean the Shaikhs', then after that you may go off by yourself, and sit in your cell alone with the Lord of Truth (Almighty and Glorious is He). When this has been fully accomplished by you, you will come to be a remedy for the people, a rightly guided guide [hadi mahdi] by permission of the Lord of Truth (Almighty and Glorious is He).
As you are now, your tongue is pious [wari'], but your heart is immoral [fajir]. Your tongue praises Allah (Almighty and Glorious is He), while your heart resists Him. Your outer being is a Muslim, but your inner is an unbeliever [kafir]. Your outer is a monotheist [muwahhid], but your inner is a polytheist [mushrik].
Your asceticism [zuhd] is part of your facade. Your religion [din] is part of your facade. Inwardly, you are a mess. It is like whitewash on the water closet, i.e. the toilet, or a lock on the garbage can. Since this is how you are, Satan has set up camp in your heart and made it a place for him to live in.
The believer starts with the development of his inner being, then tackles the development of his outer being. Someone who is constructing a house will spend large sums of money on its interior while the gateway is just rubble; he will leave fixing the entrance until after he has completed the main building. One must likewise begin with Allah (Almighty and Glorious is He) and earning His good pleasure [rida], and then pay attention to creatures with His permission. The first stage is to acquire [tahsil] the hereafter, and only then to obtain one's allotted shares [aqsam] in this world.Reference url: http://archive.islamkashmir.org/radiant-reality/jan-2006.htm#article-9