Musa was sent with the Message of Tawhid to Fir`awn and His Chiefs
Here Allah tells us about His servant and Messenger Musa, peace be upon him, and how He sent him to Fir`awn and his chiefs. That is, his governors, ministers, leaders and followers among the Egyptians and the Children of Israel. Allah sent him to call them to worship Allah alone, with no partner or associate, and to forbid them from worshipping anything other than Him. He sent him with mighty signs, such as his hand and his staff, other signs such as the flood, locusts, Qummal, frogs and blood, and the loss of their crops and lives. Yet despite all that they remained arrogant and stubbornly refused to follow him; they rejected his message and made fun of it, and laughed at the one who had brought it.
Incidents related to Sayyidna Musa (علیہ السلام) have been stated by the Qur'an at many places repeatedly, and the incidents referred to in the present verses have been described in detail in Surah Al-A` raf. The reason for reminding these incidents here is to show that the objection of the infidels of Makkah that the Holy Prophet ﷺ is not a wealthy man is not a new objection; Fir'aun had expressed the same doubt against Sayyidna Musa (علیہ السلام) and his prophethood. His contention was that being the ruler of Egypt, and owner of the palaces and rivers flowing beneath them, how could Musa (علیہ السلام) claim to be a prophet against him. But just as Fir'aun's disbelief could be of no avail to him, and he got drowned along with his people, this objection of 'kuffar' of Makkah, too, will not save them from the divine punishment in this world, or in the Hereafter.
Tazkirul Quran
Maulana Wahiduddin KhanOn ayahs 50–55
Moses presented the message of the unity of God to Pharaoh and showed him the miracles of the rod and the shining palm of his hand. On seeing this, Pharaoh and his courtiers started making a mockery of him. The reason for this was that they did not see Moses in the context of his mission but in the shape of a personality. They saw that to all appearances he was, as compared to themselves, a person of no account. Similarly, they thought that the miracles were simply feats of magic and that such magical feats could be performed by any other magician. This always happens in the case of preachers of the Truth. People reject the call of Truth by simply looking at the personality of the preacher of Truth. They ignore the signs of God, considering them likewise to be nothing out of the ordinary. When Pharaoh and his companions rejected Moses, God Almighty inflicted many admonitory punishments on them, so that they might turn back to the right path. Mention is made of these in chapter seven (verses 133-135). All these punishments were sent down, and also came to an end, in answer to Moses’ prayers. This was one more reason why they should have felt inclined to return to the right path, but they did not do so. The fact is that those who do not reform themselves on the strength of reasoning are not affected by warnings until the irrevocable punishment of the Hereafter finally engulfs them.
Uthmani text of the Madinah mushaf (King Fahd Complex). Translation: Saheeh International. Tafsir via Quran.com.