As this video shows, in the English language various colours tend to be associated with different moods or emotions.
Blue tends to be associated with sadness. If you are 'feeling blue,' you feel depressed or sad.
Red is often used in relation to anger, warnings, danger, and other heated emotions. When somebody 'sees red,' they lose their self-control and become extremely angry.
The colour green is often used when discussing illness or nausea, and, by extension, jealousy. Therefore, if you say that someone is 'green with envy,' you are implying that they are so consumed with envy, they are on the verge of being sick.
Some colours cannot be seen by people, especially if they are colour blind, but black and white are both clearly defined and distinct from each other, making them much easier to see. Therefore, if something is 'black and white,' it is straightforward and easy to comprehend.
Another thing the colour blue is associated with is uncertainty. If something 'comes out of the blue,' then it arrives unexpectedly or from an unknown source.
White is frequently linked to purity. While lying is never pure or good, a 'white lie' can be seen as the purest of all lies as it is generally not harmful and is often said out of politeness or to spare somebody's feelings.
Also linked to the colour red is blood, and by extension, murder. Originally the idea of being 'caught red-handed' implied being seen with blood on your hands after a murder, thus proving guilt. In modern times, it is used to refer to witnessing or catching somebody in the act of doing something immoral or illegal.
Black is often used to represent something evil or related to death. The term 'black sheep,' therefore, is used when describing a disruptive or unpleasant member of a group, particularly a family.