Shaykh Yasir Qadhi elaborates on the Islamic principle of commanding what is good and forbidding what is evil, as depicted in the story present in verses 163-164 of Surah Al-A'raf.
These verses are about a group of people committing sins and another group that warned them but they didn't listen. They were instead criticized for warning them because their advice was falling on deaf ears. They were told to not waste their time because they will be punished by Allah anyway in the end . but the group maintained that they were doing this so that they would have an excuse on the Day of Judgement in front of Allah SWT that they tried commanding what is good and forbidding what is evil. It is this characteristic of Muslims that sets us apart from the rest of mankind and this is why we are the best Ummah.
Allah has His La'nah is on people who do not stop each other from doing evil and who do not preach what is good, although they are very well aware about it. We should forbid evil by usage of tongue, hand and then ultimately, hate from the heart.