Allah says: `so set your face and persevere in the religion which Allah has prescribed for you, the worship of Allah Alone, the religion of Ibrahim, to which Allah has guided you and which He has perfected for you with the utmost perfection. In this manner, you will also adhere to the sound Fitrah with which He created His creation.' Allah created His creation to recognize Him and know His Tawhid, and that there is no God except Him, as we have already seen when discussing the Ayah,
مِنَ الَّذِينَ فَرَّقُوا دِينَهُمْ وَكَانُوا شِيَعًا (Among those who split up religion and became sects - 30:32) that is, these disbelievers are those who have created a difference between Natural Faith and the true religion, or they have alienated themselves from the Natural Faith, as a result of which they are divided into different sects. شِيَعًا :Shiya'an is the plural of شِیعۃ shi` ah. A group of people following a leader is called shi ah. The fact is that the Natural Faith was based on the Oneness of Allah, by following which the entire human kind should have been one solid unit and one party. But it so happened that people split out from this unity and started following the personal views of their own leaders. Since the personal views and opinions of different people may always vary from person to person, different groups of people invented their own beliefs and religion. As a consequence, people were divided into various groups and sects, and the Shaitan made them believe that they were the only people on the right path كُلُّ حِزْبٍ بِمَا لَدَيْهِمْ فَرِحُونَ (Each group is happy with what it has before it - 30:32). That is, each group is happy and contended in its own beliefs and declare others being wrong, although they all are astray and treading the wrong path.
Tazkirul Quran
Maulana Wahiduddin KhanOn ayahs 32–34
The true religion is one, and it has been revealed in its perfect form to every prophet. That religion is turning towards God, fear of God, worship of God and giving one’s attention to God with all one’s heart and soul. This is the religion of nature and it eternally pervades the inner soul of man. All prophets preached this one religion, but their followers in latter generations split it into many religions. This results from the additions made by later generations to the original teachings of Prophets. Hair-splitting innovations in beliefs, new interpretations of religion with the changing times—all these things have created many religions out of one. When these additions are made people start laying more stress on them than on the original religion, due to which different groups set themselves up in opposition to each other. One group emphasizes one set of additions, while another group empasizes another set. At last a stage is reached when the followers of a single religion become divided up into many religious factions.
Uthmani text of the Madinah mushaf (King Fahd Complex). Translation: Saheeh International. Tafsir via Quran.com.