Sweetness-and-light

noun
1.
extreme or excessive pleasantness or amiability.
2.
decorous charm combined with intelligence.
sweetness and light
noun
1.
an apparently affable reasonableness

sweetness and light definition

A phrase popularized by the nineteenth-century English author Matthew Arnold; it had been used earlier by Jonathan Swift. According to Arnold, sweetness and light are two things that a culture should strive for. “Sweetness” is moral righteousness, and “light” is intellectual power and truth. He states that someone “who works for sweetness and light united, works to make reason and the will of God prevail.”
sweetness and light
Ostentatious amiability and friendliness, as in One day she has a temper tantrum, the next day she’s all sweetness and light. This phrase was coined by Jonathan Swift in his Battle of the Books (1704), where it referred literally to the products of bees: honey and light from beeswax candles. But in Matthew Arnold’s Culture and Anarchy (1869), the term meant “beauty and intelligence.” In the 20th century, however, it was applied to personal qualities of friendliness and courtesy and to the general pleasantness of a situation, as in Working with him isn’t all sweetness and light, you know. Today it is generally used ironically, indicating lack of trust in a person’s seeming friendliness or for a difficult situation.