From Tafhimul Quran:
These introductory verses declare the Quran to be the Book of guidance: enunciate the articles of the faith (belief) in Allah, prophethood and life-after-death; divide mankind into three main groups with regard to its acceptance or rejection, believers, disbelievers and hypocrites.
Allah invites mankind to accept the guidance voluntarily and to submit to Him, the Lord and the Creator of the universe, and to believe in the Quran, His guidance, and in the life-after-death.
The story of the appointment of Adam as Allah’s vicegerent on earth, of his life in the garden, of his falling a prey to the temptations of Satan, of his repentance and its acceptance, has been related to show to mankind (Adam’s offspring) that the only right thing for them is to accept and follow the guidance. This story also shows that the guidance of Islam is the same that was given to Adam and that it is the original religion of mankind.
In this portion invitation to the guidance has particularly been extended to the children of Israel and their past and present attitude has been criticized to show that the cause of their degradation was their deviation from the guidance.
The Jews have been exhorted to follow Prophet Muhammad (peace be upon him) who had come with the same guidance and who was a descendant and follower of Prophet Abraham (peace be upon him) whom they highly honored as their ancestor, and professed to follow as a prophet. The story of building of the Kaabah by him has been mentioned because it was going to be made the qiblah of the Muslim community.
In this portion, the declaration of the change of qiblah from the Temple (Jerusalem) to the Kaabah (Makkah) has been made as a symbol of the change of leadership from the children of Israel to the Muslim community, which has also been fore-warned to guard against those transgressions against the guidance that had led to the deposition of the Jews.
In this portion practical measures have been prescribed to enable the Muslims to discharge the heavy responsibilities of the leadership that had been entrusted to them for the promulgation of guidance. Salat, fasting, Zakat, Hajj and Jihad have been prescribed for the moral training of the ummat (Muslim community). The believers have been exhorted to obey authority, to be just, to fulfill pledges, to observe treaties, to spend wealth etc. in the Way of Allah. Laws, rules and regulations have been laid down for their organization, cohesion and conduct of daily life and for the solution of social, economic, political and international problems. On the other hand, drinking, gambling, lending money on interest etc. have been prohibited to keep the ummat safe from disintegration. In between these, the basic articles of the faith have been reiterated at suitable places, for these alone can enable and support one to stick to the guidance.
These verses serve as an introduction to the prohibition of lending money on interest. The true conception of Allah, revelation, and life-after-death have been emphasized to keep alive the sense of accountability. The stories of Prophet Abraham (peace be upon him) and of the one who woke up after a sleep of hundred years have been related to show that Allah is All-Powerful and is able to raise the dead and call them to account. The believers, therefore, should keep this fact in view and refrain from taking interest on money.
The earlier theme has been resumed and the believers have been exhorted to spend in the Way of Allah in order to please Him alone. In contrast to this, they have been warned against the evils of lending money on interest. Instructions have also been given for the honest conduct of day-to-day business transactions.
The basic articles of the faith have been recapitulated here at the end of the Surah, just as they were enunciated at its beginning. Then the Surah ends with a prayer which the Muslim community needed very much at that time when they were encountering untold hardships in the propagation of the guidance.
Allah knows best.