Surah Al-Baqarah 2:257

Allah stated that whoever follows what pleases Him, He will guide him to the paths of peace, that is Islam, or Paradise. Verily, Allah delivers His believing servants from the darkness of disbelief, doubt and hesitation, to the light of the plain, clear, explained, easy and unequivocal truth. He also stated that Shaytan is the supporter of the disbelievers who beautifies the paths of ignorance and misguidance that they follow, thus causing them to deviate from the true path into disbelief and wickedness.

(Those are the dwellers of the Fire, and they will abide therein forever.)

This is why Allah mentioned the light in the singular while mentioned the darkness in the plural, because truth is one, while disbelief comes as several types, all of which are false. Similarly, Allah said,

(And verily, this is my straight path, so follow it, and follow not (other) paths, for they will separate you away from His path. This He has ordained for you that you may have Taqwa) 6:153,

(And originated the darknesses and the light) 6:1, and,

(to the right and to the lefts) 16: 48

There are many other Ayat on the subject that mention the truth in the singular and falsehood in the plural, because of falsehood's many divisions and branches.

Allah adalah Pelindung orang-orang yang beriman. Dialah yang mengeluarkan mereka dari kekafiran kepada cahaya iman dan petunjuk. Sedang orang-orang kafir itu, pelindung-pelindungnya adalah setan yang mengeluarkan mereka dari cahaya iman kepada kegelapan kekafiran. Mereka adalah penghuni-penghuni neraka pada hari kemudian, dan mereka kekal di dalamnya selama-lamanya.

Apabila orang kafir itu pada suatu ketika mendapatkan sedikit cahaya petunjuk dan iman, maka setan segera berusaha untuk melenyapkannya, sehingga iman yang mulai bersemi itu menjadi sirna, dan mereka kembali kepada kegelapan.

Oleh sebab itu, iman yang telah tertanam dalam hati harus selalu dipelihara, dirawat dan dipupuk dengan baik sehingga ia terus berkembang dan bertambah kuat, dan setan-setan tidak akan dapat merusaknya lagi. Pupuk keimanan adalah: ibadah, amal saleh dan memperdalam ilmu pengetahuan dan ajaran-ajaran agama Islam.