1. All cats are grey in the dark

This is an idiom that works in more ways than one.

One way of interpreting (and using) it would be similar to how we use the phrase 'what you don't know won't hurt you'.

Imagine this scenario: You are in trapped in a dark room. You realise there is also another person in the room. Both of you help each other to get out. Once you get out you realise that the other person is your enemy. But in that situation when you do not know, it did not matter who the person is.

Now, look at this dialogue

John: The food is terrible, how are you eating it.
Joe: I have Covid-19 I lost my sense of taste. All cats are grey in the dark I guess.

In the conversation above, since Joe cannot taste the food, it does not matter whether it is tasting bad or good.

2. A short prayer penetrates heaven

This is something we tell all our students who are trying to improve their writing score. The advice we give is, do not include irrelevant information.

In other words, we ask them to KISS 💋. Nope, not that kiss. That was just to grab your attention. It means Keep It Short and Simple (or Keep It Short, Stupid).

Example:
Shreya says too much to convey a tiny piece of information. We all get so bored. She does not seem to understand that a short prayer penetrates heaven.

3. The chickens have come home to roost

A variation on what you sow is what you reap.

Example:
The company kept borrowing money in the hopes that market situation will improve. But it did not. Now, the chickens have come home to roost. All its debtors are asking the company to return the funds it borrowed.

Example:
Despite having a lot of time, he did not prepare for the exam. The results came, and to his horror, the chickens came home to roost. Everyone else but him passed the exam.

4. A good payer is master of another's purse

In other words, when you keep your promises, people will trust you. The full explanation is this: If you borrow money and pay it back as you promised, people will not hesitate to give you money when you ask them the next time.

If you however keep delaying and return the money late, people will not lend you money the second time.

5. A watched pot never comes to boil/never boils

When your watching water while it is coming to boil,  it seems to take a very long time. In the same way, anything that we are eagerly waiting for (a birthday, the delivery of a new phone, etc) it seems to take a long time.

In short, when you are waiting, the time seems to pass extremely slowly.