Complex sentence: Art historian Maximiliaan Martens has suggested that the painting could have been intended as a gift for the Arnolfini family in Italy, since it had the purpose of showing the prosperity and wealth of the couple depicted.
Split into simpler sentences: Art historian Maximiliaan Martens has suggested that the painting was meant as a gift for the Arnolfini family in Italy. It had the purpose of showing the prosperity and wealth of the couple depicted.