Once I was on a journey. I met a person who was from Japan. He said that he was studying at a university in Japan and doing research. He was researching on silence. Silence was the topic of his research. He studied what different religions had to say on the importance of silence. When he informed me that he was studying silence, I told him about a saying of the Prophet of Islam. 
Copy Arabic text (Sunan al-Tirmidhi 2501)
"One who remains silent finds salvation." The Japanese immediately wrote down this hadith. This hadith tells us half of wisdom. It tells us something very important: There are times when remaining silent is more important than speaking. There are times when not doing anything is taking an action. There are times when speaking means to remain silent. This is a great science. The Japanese understood the importance of this hadith. He took it with great interest. He asked me about the translation and meaning of the hadith. We need to reflect on the wording of the hadith: One who remained silent, finds salvation.  Salvation is the greatest thing. The Prophet connected salvation with silence. Being silent is not inaction. Being silent is not lack of action. You can do a lot by remaining silent. This is the great wisdom given in this hadith. Being silent means to not speak without thinking. You should have the quality of not speaking without thinking. If you want to speak, think first. 
What is the meaning of 'one who remains silent finds salvation'? What is the meaning of being silent?
You should think before speaking. This is great wisdom. 
The Japanese told me that being silent means to think before speaking. You should plan before taking an action. Before jumping to take an action, you should draw up a plan of action. You should assess the situation. All this is included in the hadith, 'One who remains silent, finds salvation.'