Is it obligatory to say before the taslim (O Allah, I seek refuge in You from the punishment of Hell… etc.), and what is the meaning of: (the trial of life and death)?

Question:
What is the ruling on our saying in the final tashahhud of the prayer? Is it obligatory to say this du'a, such that leaving it out is forbidden? Is it obligatory to say this du'a, and does leaving it out invalidate the prayer? Or is it a sunnah? And what is the meaning of "the trial of life and death"? May Allah reward you with good.

Answer:
In the name of Allah, the Most Gracious, the Most Merciful. Praise be to Allah, Lord of the worlds, and may Allah send prayers and blessings upon our Prophet Muhammad, and upon his family and his Companions. To proceed: The du'a, and seeking refuge from these four things in the final tashahhud before the salam, is a sunnah (recommended practice) and not obligatory. If one leaves it out, his prayer is valid. If one performs it, it is more complete, and there is great reward in it. It is a great du'a that the Muslim needs, and the Prophet (peace and blessings be upon him) recommended it. He said, "Seek refuge in Allah from these four." This matter indicates that the default is that it is for obligation, but here it is for recommendation; because the Prophet (peace and blessings be upon him) did not teach it to the one who was deficient in his prayer, to whom the Prophet (peace and blessings be upon him) explained what is obligatory for him in his prayer. This indicates that it is recommended.
And the meaning of "the trial of life and death": the trial is the test and the examination. "Life" refers to the life of the person in this world, before death. He is exposed to trials that turn him away from the religion of Allah (Mighty and Majestic). So he asks Allah for steadfastness and to protect him from the evil of the trials that occur to him in this world, and how many there are, especially in the end times, when trials increase and the danger becomes great. As for the trial of death, it refers to what befalls the deceased at his death. He may be sealed with a bad ending and die upon other than Islam. And also what happens after death in the grave, the questioning by the two angels. When he is placed in his grave, they ask him: Who is your Lord? What is your religion? And who is your Prophet?
This is part of the trial. If he answers with a correct answer, saying, "My Lord is Allah, my religion is Islam, and my Prophet is Muhammad (peace and blessings be upon him)," he is saved and successful. If he stammers and cannot answer, and says, "Ah, ah, I do not know," then he has failed and lost, and the punishment descends upon him in his grave and after his resurrection, and may Allah protect us from that. The trial is very severe. And also what happens in the grave of punishment or bliss, for the grave is either a garden from the gardens of Paradise or a pit from the pits of the Fire. Yes.