It may have started to snow in Milan on Sunday afternoon, but at Dolce & Gabbana’s show HQ the climate was anything but cold.

This season, design duo Domenico Dolce and Stefano Gabbana made a declaration of love to the industry with an autumn/winter 2018 collection entitled Fashion Devotion. While they are well known for their dedication to their craft, one half of the design duo was in a particularly enthusiastic mood at a preview hours before the show.

“Fashion is not work, fashion is devotion,” Dolce said. “You live, sleep and eat with fashion, you never stop thinking about it and you love it with all your heart.”

Models on the catwalk for Dolce & Gabbana Photograph: Miguel Medina/AFP/Getty Images

On the catwalk, this was expressed using religious iconography – a frequent theme in the house’s collections – with gold embellished tabernacle bags, embroidered haloes, dog-collar shirting and, most distinctively, the sacred heart. This was found on dresses, coats, and came as a sculpted clasp on the brand’s new bags, which were flown in on drones like robotic angels before the models appeared. Divine inspiration also materialised in T-shirts that read Fashion Sinner. The designers are heavily involved with the Metropolitan Museum of Art’s forthcoming Costume Institute exhibition, entitled Fashion and the Catholic Imagination, for which this collection is one to explore.

There’s no doubt that the exquisitely executed pieces in this show, featuring over 100 models, will cost a lot of money – prices start from about £150 for a bikini top and stretch to £9,000 for an embellished gown – but backstage, Dolce insisted money was the last thing on his mind. “You kill the love and creativity when you talk about how much something is,” he said. “When the creativity is beautiful, the people pay.”

Based on the results, the designer appears to be right. The house turned over €1.3bn (£1.1bn) in the 2016-17 financial year, a 9% increase on the previous year.

Model Manuela Sanchez for Marni during Milan fashion week Photograph: Pietro D'Aprano/Getty Images

Earlier in the day, the concept for autumn/winter 2018 was more subtle. At Marni, the Italian house known for its conceptual approach and art influences, Francesco Risso, its creative director, invited guests to watch his third collection sat on televisions, compact newspapers, and rugs piled high.

“Basic, raw and immediate,” as the show notes advised, the clothes here had trailing loose threads and visible inverted seams for deliberate slapdash effect. Striped blanket coats, colour-clashing silk and sequinned dresses, and long ribbed polo necks were bunched, wrapped and joined with pins and hardware, “fusing halves together”.

Elsewhere, memorable motifs came by way of coats with an all-over camouflage print made up of women’s faces, illustrating “safety in numbers”, as well as a whiskered cat print with eyes designed to “hypnotise and attract all over”.