An aspect of "Believing in Yourself" is to believe in your intelligence, and in your ability to make decisions. There are people who follow the crowd, and do whatever everyone else is doing because they are afraid to think for themselves and make their own decisions. When they see people speaking during prayer, they join them, because they are afraid to think for themselves. When they see people praying as quickly as possible, they follow the trend, although they know that it is wrong. The reason is because they don’t trust themselves. They don’t believe that the mind Hashem gave them has validity. It states (I Kings 2:1-3), "When the days of David's life were coming to an end, he commanded his son, Shlomo, saying, 'I am going in the way of all mankind. Be strong. Be a man…" The Chasam Sofer says that David was telling Shlomo, "When you see people sinning, don’t say that you will follow the ways of the world and sin together with them. Be strong, be a man, and do what's right." Similarly, when you see people lax with Torah and prayer, don’t say you will do what others do. Be strong, be a man, and do what you know you should.
Someone opened up a fish store, and put up a large sign: "Selling Live Fish Here." Someone came by and said, "You need not write that the word "Here" on your sign because everyone knows you are selling your fish here and not at home. So, the storeowner erased the word "Here". Someone else came and said, "You don’t have to write that the fish are alive. Of course they are. No one sells dead fish. (That was true, before refrigerators and freezers were invented). The word "Live" is extra in your sign." The storeowner erased the word "Live." Yet someone else came by and said, "The word 'Selling' is extra. No one will assume you're giving away fish for free. You should erase that word. All you need to write is 'Fish.'" He followed this counsel and now the sign just said "Fish." Someone came by and said, "The odor of your fish store can be smelled all the way down the block. Everyone knows you're selling fish. So, the word 'Fish' in your sign is extra." Once again he followed the counsel and erased the word "Fish." Now he had a store without a sign. People stopped coming, and he had to close the store. The moral of the story is that a person shouldn’t follow the counsel of others, just because "they said it." If it isn't good counsel, don’t listen. Hashem gave you intelligence, and it was given to you because you have the capability of using it, so you can lead your life in the way you know is best. If you don’t like a certain food, and you even find it disgusting, will you eat it anyway, just because all your friends are eating it, and they say it's delicious? Of course you wouldn’t. Why do you follow what others say and what others do, even when you know in your heart that it isn't good for you? Why don’t you follow your common sense?
Note: The end of the verse is, "Guard Hashem's Torah, to go in His ways…" The Chasam Sofer says that this isn't referring to the laws of the Torah, such as wearing tzitzis and putting on tefiin, because those mitzvos are written in the Torah and David wouldn’t need to warn Shlomo to keep them. Rather, David was referring to the protective guards that distance people from sin; the boundaries, which help one go in Hashem's ways. David urged Shlomo to keep those guards, so he can go in the ways of the Torah.
Years ago, it was common for a Jew would rent a kretchme (a hotel, bar, restaurant) from a poritz. Our story is about a Jew who rented one such kretchme. When the poritz came at the end of the year to collect the rent, the Jew told him, "You know that this has been a very harsh winter and a snowy year. Few people traveled. The hotel was empty most of the year. I didn’t earn enough money to pay the rent. But next year, I will pay you two years rent, with a bonus." The poritz agreed and left. But the next year was even more snowy and wintery than the previous year. Once again, he didn’t have enough money to pay the rent. He realized that his life was in danger, because the poritz of that era had permission to do whatever he wanted to the people under his rule. So the Jew had no other choice other than to escape. The family packed their belongings onto a wagon, and in the middle of the night began their escape. As they were traveling, whom should they meet, none other than the poritz himself. He was traveling in the other direction, and they stopped in the middle of the road to speak with each other. "I don’t believe this! Where are you going? The rent is due in a couple of days!" The Jew didn’t lose his composure. He replied, "Don't worry about the rent. I have two years' worth of rent all bundled and prepared for you. But right now I'm going to the city to celebrate yom tov (Jewish holiday) with my family. As you know, us Jews often travel to be with our families for the holidays…" The poritz looked perplexed. He asked, "I know when Pesach, Shavuos, and Succos is, but I didn’t know there's a holiday this time of year." The Jew told him, "Of course there is. Tomorrow is a holiday called יום פליטנו (literally, 'the day we escape). The poritz replied, "Never heard of it before, but you learn new things every day. Enjoy your holiday. I'll meet you at the kretchme in a couple of days." They said goodbye and they each went on their way. The next day, the poritz saw Jews working as usual. He asked one of the Jews, "Why are you working? My Moshke (Jewish tenant) told me you have a yom tov today." The Jew immediately realized that he must cover up for a fellow Jew, so he replied, "Oh, that's right! How could I forget. It's a yom tov! By the way, do you remember the name your Moshke gave for this yom tov?" "I do. He called it "the day of escaping." "Yes, of course. Let me tell you the difference between this holiday and all other holidays. Most holidays are on a set day, but this is a holiday that everyone celebrates on his own day." What we learn from the parable is, the days we escape from the yetzer hara (Evil Inclination), with our own protective guards - by being cautious with our eyes, speech, etc., is our "day of escaping." Everyone celebrates this holiday on the day they succeed to free themselves from the pull of the yetzer hara.