And when it is said to them (hypocrites): "Believe as the people (followers of Muhammad Peace be upon him , Al-Ansâr and Al-Muhajirûn) have believed," they say: "Shall we believe as the fools have believed?" Verily, they are the fools, but they know not. (2:13)

Allah is mentioning that we should see the examples of the companions of the Prophet, and how they sacrificed their lives, status, wealth, families, and their relatives in order to practice Islam. Saying one is Muslim and does not practice the law of Islam, one may ask how can that individual be one of them. And this is how we are being warned by Allah.  Sometimes people would be under the impression that these things are outdated, and would sympathies with a practicing Muslim, also thinking that these people are fools and left over from society. How can they be fools and left over from society? Those are the people who prepare themselves for the hereafter, meaning after death. Because the life of this world, is only temporary no one knows the actual length of their life, but in the hereafter the time is never ending, and there is no solar system for a dead person. And for eternity we will never die again, so we can imagine now who are the fools, it's people, who do not prepare for the next second which can occur as death. All of their worries, efforts, and powers are only used towards this world, which they will leave in one second, and there will be no one there to take care of them, no relatives, mother, father, or money, will ever help. As we know when someone passes away no one wants to come close to that person, or stay with that person in the grave yard any longer than burying him. We know that billions have already faced death, and we are on the same track also. The dead person we are sympathizing for now, we should never forget that tomorrow someone will be sympathizing for us.  Don't be fooled by Satan, who just gives us assurance, and guarantees only through power, money, and security by governments, but these governments are all human beings also, once we die no one will put life in to our dead bodies. Practice is very important for those who claim to be Muslims, being a Muslim who denies and ignores the laws of Allah, and the examples of the Prophet, then he or she is fooling themselves. Many such as Hitler came and killed many people, where is he today, the man who use to be proud of his power and status?

So prepare yourself and those who you claim to love the most, such as your children, wife, or immediate family, for the hereafter.

Note: However the doors of repentance are never closed until death, and we should cry and beg to Allah in order to open our eyes and hearing so we can understand the orders of our creator, sustainer, and our provider, we should always remember that Allah's mercy is more stronger then his punishments, if one tries to seek it within his lifetime, inshallah.