In western culture, Friday is regarded as a special day, because Friday is usually the last day of work and the beginning of weekend holidays. Therefore, Friday is also called Friday.
This proverb probably originated in ancient China. In the ancient culture of China, gold was regarded as a lucky color, and Friday was also regarded as a lucky star. Therefore, combine these two forms of this proverb.
Now, this idiom is usually used to mean that Friday is a particularly lucky day, which may bring good luck or good things. It can also be used to express expectations or wishes for Friday.