Muslims must fear Allah and take lessons from what Allah has told us in the Qur’an regarding the Prophets and Messengers of Allah and the previous nations.
Allah said (which means):
“Indeed in their stories, there is a lesson for men of understanding. It (the Qur’an) is not a forged statement, but a confirmation of Allah’s existing books (the Torah, the Injeel, and other Scriptures of Allah), a detailed explanation of everything, and a guide and a mercy for the people who believe.” (Yusuf 12: 111)
And among the stories that Allah has narrated to us in His Book is what happened in Allah’s month,(1) the sacred month of Moharram,(2) and that is the story of Prophet Moosa, and Pharaoh the tyrant of Egypt, in the Qur’an, Allah tells us this story, which means,
“We recite to you some of the news of Moosa and Pharaoh in truth, for a people who believe (i.e. those who believe (ie those who believe in this Qur’an and in the Oneness of Allah). Verily, Pharaoh exalted himself in the land and made its people sects, weakening (oppressing) a group (Bani Israa’eel) among them, killing their sons and letting their females live. Verily, he was of the mufsidoon (those who commit great sins and crimes, oppressors and tyrants). And We wished to do a favour for those who were weak (and oppressed) in the land, and to make them rulers and to make them the inheritors, and rulers and to make them the inheritors, and to establish them in the land, and We let Pharaoh and Haamaan (a minister of Pharaoh) and their hosts receive from them that which they feared.” (Al-Qasas 28:3-6)
Pharaoh dominated the nation of Israa’eel and enslaved them, killing their newborn sons but letting their females live. The reason he committed this criminal act was the fear of the truth coming out from one of those newborn males. The nation of Israa’eel used to know, according to what came to them from Prophet Ibraheem, that someone from his lineage would destroy the king of Egypt. These glad tidings were famous among the nation of Israa’eel; and the news of it was made known to Pharaoh. Pharaoh ordered his soldiers to kill all newborn boys of the nation of Israa’eel; on order to secure himself from destruction.
However, all of the precautions that he made were not enough to protect him from what Allah wanted, which was for this newborn boy to be raised in the house of Pharaoh. The will of Allah cannot be stopped by any precautions and His ability conquers anything. So Allah chose for the Prophet Moosa to be born safely, to be saved from being killed, and also to be raised in Pharaoh’s own home under the protection of Allah until he was an adult.
Later Moosa accidentally killed a person from Pharaoh’s people. Moosa was afraid that he would be captured and be killed for this, so he fled to the land of Madyan and abided there for some time. He married there and then returned to Egypt. On the way back Allah talked to him (by wahy)(3) revelation and told him he was a prophet and the Messenger to Pharaoh. Allah told him many signs by which he will be known as the prophet of Allah and they would show that he was a true prophet.
Moosa went to Pharaoh and showed him the signs of Allah but Pharaoh was arrogant and stubborn.
Allah says (which means):
“Has there come to you the story of Moosa? When his Lord called him in the Valley of Tuwaa. ‘Go to Pharaoh, verily he has transgressed all bounds (in crimes, sins, polytheism and disbelief). And say to hi, ‘Would you purify yourself (from the sin of disbelief and by becoming a believer). And that I guide you to your Lord, so you should fear him?’ Then (Moosa) showed him the great signs (miracles). But (Pharaoh) belied and disobeyed; then he turned his back, striving hard against (Allah). Then he gathered his people and cried aloud, saying, ‘I am you lord, most high.’’’(An-Naazi’aat 79: 15-24)
Pharaoh claimed that the signs Moosa brought were only magic and that he had magic that would overtake the magic of Moosa. So Pharaoh gathered magicians from his kingdom and they presented their magic, and Moosa presented what he had from the signs, which Allah had given him.
Allah said (which means): 
“Thus truth was confirmed, and all that they did was made of no effect. So they were defeated there and then, and were returned disgraced. And the sorcerers fell down prostrate. They said, ‘We believe in the Lord of the ‘Aalameen (i.e. all that exists), the Lord of Moosa and Haaroon (Aaron).’” (Al-A’araf 7: 118-122)
At that time Pharaoh decided to try a different plan - fear, force and retaliation. Allah told Moosa to get every believer out of Egypt and direct them to where Allah would tell him. Pharaoh gathered his army and forces, which were around one million soldiers according to the seerah, and he chased Moosa and his people, hoping to destroy them completely. Moosa ended up at the sea with Pharaoh and his army behind him. The believers were afraid because the sea was in front of them and the enemy was behind them.
Allah says (which means):
 “And when the two hosts saw each other, the people of Moosa, said, ‘We are sure to be overtaken. (Moosa) said, ‘Nay, verily! With me is my Lord and He will guide me!’” (Ash-Shu’araa 26: 61-62)
Whoever is close to Allah, Allah will never let him down or leave him on his own. Allah ordered Moosa to strike the sea with his staff. Moosa did so and the sea opened up for them to cross:
Allah says (which means):
 “And indeed We inspired Moosa (saying): ‘Travel by night with ‘Ibaadi (My slaves) and strike a dry path for them in the sea, fearing neither to be overtaken (by Pharaoh) nor being afraid (of drowning).” (Taaha 20: 77)
Moosa walked across the path that opened in the sea and the last of his people left the sea and every soldier of Pharaoh’s army was inside the path. At this time Allah ordered the sea to collapse upon them, drowning Pharaoh and his army.
That was the victory of the truth over falsehood. The promise of Allah was true - He made the people of Moosa victorious over Pharaoh and his army. From this story we see how the truth is victorious, regardless of the size or seeming power of falsehood. Falsehood has its own limited time, but the truth is always victorious. This story should enrich the hearts of the believers and make them steadfast in the face of their enemies, regardless of size or seeming power of their enemies. 
The believer should also benefit from this story by understanding that the people of falsehood claim that they are on the right path and are calling people to the truth. In fact, the opposite is true-they rely on lies and deception.
Pharaoh said to his people,
“I guide you only to the path of right policy!” (Ghaafir 40:29)
But he was a liar. From this story we also see that whoever knows the truth and truly believes in it will not lose, regardless of what he or she endures of torment, torture or even death. An example is of the magicians. When they knew the truth, they believed in Allah and in the message of Moosa.
Allah says (which means):
 “So the magicians fell down prostrate. They said, ‘We believe in the Lord of Haaroon and Moosa.’” (Taaha 20:70).
Pharaoh threatened to crucify them, but they were strong in their belief and refused to return to disbelief after believing.
Allah said (which means): “Pharaoh said, ‘Believe you in him (Moosa) before I give you permission? Verily! He is your chief who taught you magic. So surely I will cut off your hands and feet on opposite sides, and I will surely crucify you on the trunks of palm-trees, and you shall; know which of us, (I, Pharaoh) or the Lord of Moosa (Allah) can give the severe and more lasting torment.’
They said, ‘We prefer you not over the clear signs that have come to us, and to Him (Allah) who created us. So decree whatever you desire to decree, for you can only decree (regarding) this life of the world.’
‘Verily! We have believed in our Lord, that He may forgive us our faults, and the magic to which you did compel us. And Allah is better (as regards in comparison to your punishment).’
Verily! Whoever comes to his Lord as a mujrim (criminal, sinner, polytheist, disbeliever in the oneness of Allah and in His messengers) then surely, for him is Hell, therein he will neither die nor live. 
But whoever comes to Him (Allah) as a believer (in the oneness of Allah) and has done righteous deeds, for such are the high ranks (in the Hereafter).” (Taaha 20:71-75) 
We also derived from this story the lesson that falsehood, regardless of how big or the number of its adherents, will be defeated by the truth and the people of the truth are patient with whatever they are facing. This is an example of an arrogant tyrant with power, an army and a kingdom which he ruled, who pursued a few who had no munitions or other means (of defence), but Allah was with them and they had the force of Imaan in their hearts. Allah gave them His victory, His guidance, His help; and in a single moment the forces of falsehood were destroyed. Pharaoh’s forces were destroyed in the sea and as Allah said (which means):
 “We fling (send down ) the truth against the falsehood, so it (truth) destroys it, and behold, it (falsehood) is vanished.” (Al-Anbiyaa 21: 18)
We also learn that Allah tests the prophets and the believers, and the tests are sometimes very difficult, but in the end, victory is for the prophets and the believers. Allah is with the prophets and the believers in victory and guidance.
Allah says (which means):
“Truly, Allah is with those who fear him, keep their duty unto Him, and those who are Muhsinoon (doers of good, those who perform good deeds solely for the sake of Allah and in accordance with the Sunnah of the Prophet).” (An-Nahl 16: 128)
As Muslims, we should always fear Allah and consider these lessons and not follow the ways of those who were disobedient to Allah; but rather to obey the Prophet and follow his guidance as Allah told us, which means,
 “Indeed in the Messenger of Allah (Muhammad) you have a good example to follow for him who hopes in (the meeting with) Allah and the Last Day and remembers Allah much.” (Al-Ahzaab 33: 21)
This great event - the victory Allah gave Moosa and the believers over Pharaoh and his army - occurred on the 10th of the sacred month of Moharram and the day is called Yaumul Aashoorah (the day of ‘Aashoorah). It is a day that has great merit. Prophet Moosa fasted on that day, and ordered the people to fast that day. 
Ibn ‘Abbass reported that when the Messenger of Allah (sallallaahu ‘alaihi wa sallam) arrived in Madinah, he found the Jews fasting on the day of Aashoorah. The Messenger of Allah asked them, “What is the significance of this day that you fast on?” They said, “It is the day of great significance when Allah delivered Moosa and his people and drowned Pharaoh and his people. Moosa observed fast out of gratitude, and we also observe it.” Upon this, the Messenger of Allah said, “We have more right and we have a closer connection (awlaa) to Moosa than you have.” So Allah’s Messenger fasted (on the day of ‘Aashoorah ) and gave orders that it should be observed.(4)
According to Muslim, the Prophet (sallallaahu ‘alaihi wa sallam) said of fasting on ‘Aashoorah that “It is an expiation (of sins) for the previous year.”(5)
According to many authentic ahadith, fasting on ‘Aashoorah was obligatory, but later made voluntary when the obligation of fasting the month of Ramadan was revealed in the Qur’an.(6)
The Prophet fasted on the day of ‘Aashoora and commanded that people should fast on that day. The sahaabah (his companions) said, “Messenger of Allah, it is a day which the Jews and Christians hold in high esteem.” Thereupon the Messenger of Allah said, ‘“When the next year comes, inshaa ‘Allah, we would fast on the 9th (i.e. the ninth as well as the 10th in order to differ from the disbelievers).” But the Messenger of Allah died before the advent of the next year.(7) Therefore we should fast that day and one day before it (the 9th), following the Prophet’s Sunnah and looking for the reward from Allah.(8)
We also benefit from the story of Moosa by learning that the Sunnah of the Prophets is to thank and praise Allah in times of peace and when they gain victory over their enemies. Moosa fasted on the 10th, the day on which Allah made his followers victorious over Pharaoh; and this is another sign that the truth will always defeat falsehood.
The Prophet fasted on this day thanking Allah for the victory of the people of the truth over the people of falsehood. The victory in that time was for Moosa, but the Sunnah of the prophets is one. This is the jihaad against the disbelievers - to make the Word of Allah the highest on earth. Victory always comes from Allah and victory is a ni’mah (bounty) from Allah for which we must thank Allah by being obedient to Him.
Some people nowadays create bid’ah (innovation in the deen), and deviant slogans and hold demonstrations. Islam has forbidden this. 


NOTES:
1 The Prophet said, “The most excellent fast after Ramadan is Allah’s month, Moharram, and the most excellent prayer after what is prescribed is praying during the night.” (Saheeh Muslim, Volume 2 page 569 no.2611 )
2 The sacred months are four: Dhul-Qa’dah, Dhul-Hijjah, Moharram and Rajab. See Qur’an, At-Tawbah 9: 36-37. Waging war, killing and plunder are prohibited during these months. It is prohibited to intentionally violate the sanctity of one of the months and then make up for it, as the pre-Islamic Arabs used to do in order to give themselves a military edge. However, if you are attacked during one of these months, it is permitted, as mentioned in the ayah 2:194 to attack them as you were attacked. 
3. by revelation
4 Saheeh Muslim, Volume 2 page 551 no. 2520
5 Saheeh Muslim
6 Saheeh Muslim, Volume 2 page 548 no. 2499
7 Saheeh Muslim, Volume 2 page 552 no. 2528
8 We may only single out this day as a day of fasting and not a day of celebration. Abu Moosa reported that the people of Khaybar (most of them were Jews) observed fast on the day of ‘Aashoorah and they treated it as “Eid and gave their women ornaments and beautiful dresses to wear. The Messenger of Allah said, “You (only) fast on this day.” (Saheeh Muslim)
Related Story