We have made it a reminder1 and provision for the travelers,2
Translation: Saheeh International (English)
1 Of the great fire of Hell.
2 In the form of flints or other means by which to ignite fire. Travelers are mentioned because of the special convenience to them, although it is a provision for all people in general.
لِّلۡمُقۡوِينَfor the wayfarers in the desertlil'muq'wīna
Tafsir
I am the one who made this fire for you as a reminder to you of the fire of the Afterlife, and I made it a means of benefit for the travellers among you.