By cleanliness we mean the habit of keeping physically and mentally clean.
A smartly dressed person with clean habits creates an impression on others. It usually reflects a clean character also. In other words, a person’s character can be assessed by the way he dresses.
If he is carelessly dressed, he will most probably be an unruly person. Similarly, if he is in the habit of dressing smartly, he tends to be clean in character also. This is the general rule although there are exceptions to it.
Men with good character are usually pious and god-fearing. They stick to certain morals in their life. Thus, having a god fearing or clean heart is the first step to being godly. In other words, godliness should begin from the heart.
One can have a clean heart only if he cultivates a good character. In other words, a good heart is moulded from a good character.
All religions insist on cleanliness before worship. This is because cleanliness is the first important thing in being near to god.
This proves that the proverb cleanliness is next to godliness is true to the core.