Aliud eiusdem argum.

This poem references the Miracle of the Snow at Santa Maria Maggiore in Rome. According to church tradition, on August 4, 352 C.E., a patrician named John and Pope Liberius each dreamt that the Virgin Mary commanded them to build a church where snow was found. They found the top of the Esquiline hill miraculously covered in snow the next morning. This church would eventually become Santa Maria Maggiore, also known as Basilica S. Mariae ad Nives. The miracle was commemorated annually on August 5th.

Has tibi¹ Virgo nives Coeli dimittit ab hortis, Non potes aestivas Roma² timere faces.

In the title: argum = argumentum ¹ Referring to Roma in the second line. ² Vocative.