Four Fundamental Principles Concerning Daʿwah
Written in a simple and lucid way, this brief account describes the general methodology that is an obligation to be followed by every Muslim in his/her Daʿwah to Allāh.
So therefore, this is the accurate depiction of an enormous illustration, clarifying that which it is obligatory for the Muslim to be upon from a knowledge-based practical application of Islām in a way which will be pleasing to Allāh the Exalted.
Indeed, it is obligatory upon every Muslim to know four matters and to act upon them, and these matters are: [i] Knowledge; [ii] Acting upon it; [iii] Calling to it; [iv] Being patient with the hardship encountered due to it.
Indeed, an incitation towards these four matters has occurred in Sūrah al-ʿAṣr:
“By the time, verily man is in a state of loss. Except those who believe and perform righteous deeds, and advise each other to the truth, and advise each other to patience.” [Sūrah al-ʿAṣr, 103:1-3]
So indeed Allāh the Exalted swears by the time, and Allāh the Exalted can swear by anything from His creation, contrary to the creation itself. So it is not permissible for the creation to swear, except by Allāh the Exalted, or by an Attribute from His Attributes. And the answer of this swearing is that: “…verily man (al-Insān) is in a state of loss.” And ‘al’ in al-Insān means definitiveness. That is to say, all of mankind are losers, except those who can be described with these four characteristics. So these bring one out of the state of loss, and these four characteristics comprise al-īmān (faith). So there is no doubt that this īmān must be built upon knowledge. And this knowledge is the recognition of Allāh the Exalted by His Attributes, and the recognition of His Messenger (ṣallallāhu ʿalayhi wa-sallam), and the recognition of the Religion of Islām by its proofs. So action must follow this knowledge by way of statement, deed, and belief. Allāh the Exalted said:
“So know that there is no deity worthy of worship besides Allāh, and repent for your sins.” [Sūrah Muḥammad, 47:19]
Indeed Imām al-Bukhārī (d.256H) – raḥimahullāh – inserted a chapter in his book to illustrate this, so he said: “Chapter: Knowledge comes before statement and action.”  So Allāh pointed out the second matter by His statement: “…and do righteous deeds…” So knowledge without action is like a body without a soul. Therefore, there can be no benefit in it, rather it becomes an argument against its owner. Allāh the Exalted said:
“O you who believe! Why do you say that which you do not do? It is extremely hateful to Allāh that you say that which you do not do.” [Sūrah al-Ṣaff, 61:2-3]
So the action cannot be righteous, except if it is done purely for Allāh, in accordance to the Sharīʿah of Allāh. Then Allāh pointed out the third matter by His statement: “…and advise each other to the truth…” This refers to daʿwah (calling to Allāh) upon knowledge, wisdom and a good preaching, as Allāh the Exalted said:
“Say: This is my way, I call unto Allāh with sure knowledge. I and those who follow me, and I am not from amongst the polytheists.” [Sūrah Yūsuf, 12:108]
Then He pointed out the third matter by His statement: “…and advise each other to patience.” Therefore, it is inevitable that the one who calls to Allāh must be patient and take into consideration that which he will encounter of hardship along the way of teaching and calling to Allāh. So he must follow the path of the Prophets and Messengers and become patient where they were patient, until the call to Allāh has been conveyed; despite whatever he encounters from hardship in that.
So therefore, this is the accurate depiction of an enormous illustration, clarifying that which it is obligatory for the Muslim to be upon from a knowledge-based practical application of Islām in a way which will be pleasing to Allāh the Exalted. Imām al-Shāfiʿī (d.204H) – raḥimahullāh – said: “If Allāh had not revealed any proof to His creation other than this sūrah, it would have been sufficient for them.” 
 The following is taken from Mukhkiratun fil-’Aqīdah (p. 57-58) of Shaykh Ṣāliḥ al-Suḥaymī.
 Refer to the Ṣaḥīḥ of al-Bukhārī (1/159).
 Related by Ibn Kathīr in his Tafsīr (8/500)
Translated by Maaz Qureshi