Overall meaning : Allah Almighty states that the ritual of walking back and forth between the hills of Safa and Marwah are some of the apparent symbols and salient features of His religion  that have been prescribed for the performance of the pilgrimage (hajj), pointing out that whoever sets out for the Sacred Mosque intending to perform the major pilgrimage (hajj) or minor pilgrimage (‘umrah) should not have any feelings of guilt about walking between them in view of the fact that they used to worship idols by them before the advent of Islam.
In order to arouse His servants’ interest in acts of obedience and encourage them to carry out more of them, Allah Almighty states that whoever carries out an act of obedience, be it obligatory or voluntary, and does more of it will certainly be repaid the best reward for it; for Allah, Exalted be He, is All-Appreciative, who does not let good works go unrewarded; All-Knowing, who has full knowledge of people’s good works.
In the context of rebuke and criticism, Allah makes mention of the learned among the Jews and Christians who do not show people the clear proofs in the Torah and the Gospel that establish and confirm the prophethood of Muhammad, may Allah bless him and grant him peace, and mention his description. In fact, such rebuke and criticism is directed at all those who follow in their footsteps and endeavour to conceal the truth Allah has revealed in the Qur’an after He, Exalted be He, has made it abundantly clear. As a requital for this, these will be excluded from Allah’s mercy, and the angels and believers—or maybe all creation—will invoke Allah to exclude them of His grace, except for those who refrain from concealing the manifest truth, turn to their Lord in repentance, acknowledge their sins and make up for them by openly declaring to people the truth which they have previously concealed. Allah informs us that He will accept their repentance, for He is the One who accepts people’s repentance after leading them to it, Most-Merciful to them.
Regarding those who reject His religion, wilfully turn away from it, do not repent and persist in their unbelief until they die, He affirms that He will permanently exclude them from His mercy and grace, and states that they will incur His curse and that of the angels and all mankind, and that such curse will remain with them in their lives and all the way to the Day of Resurrection, to remain with them in Hell, where torment will not be lightened for them, nor will they be granted a respite or a reprieve from punishment.
The Almighty then proclaims that the only God deserving of worship is One and has no partners whatsoever, namely Allah, Exalted be He, who possesses immense, limitless mercy which He extends to all His creation.