What is the meaning of the word "al-umthul" in the hadith of Mu'adh: "The most severe trials are for the prophets, then for the next best, then for the next best"?

The questioner : Shaykh, may Allah reward you. Imam Ahmad narrated from Mu'adh ibn Jabal: So what is meant by the last "al-umthul"?

The Shaykh : The most severe trials are for the prophets, because Allah (Glorified and Exalted is He) tested them with prophethood, tested them with calling to Allah, and tested them with people who deny them and describe them with characteristics of criticism and blame, as Allah the Exalted said: . However, this trial is actually a blessing, because everything that befalls them as a result of it is an elevation in their ranks. This means: the best, then the best. The better a person is, the stronger he is in his call to Allah, and the more firmly he holds to the religion of Allah, the more enemies he has. Allah the Exalted said: . The enmity of the criminals toward the prophets is not for their persons, but for the truth they brought. Accordingly, whoever holds to the truth they brought will face enmity from the criminals similar to what the prophets face, or less, depending on the situation.
And Allah (Mighty and Majestic) is Wise; He tests with blessings and He tests with hardships. He tests with blessings to see whether we will be grateful or ungrateful, and with hardships to see whether we will be ungrateful or patient. This is the meaning of the hadith. In reality, this is a consolation for the believer and the caller to Allah when he is met with what he is met with from people; indeed, that is in the path of Allah. And when the Messenger of Allah (peace and blessings be upon him) had his finger bled, he said: So know that everything that befalls you of mockery or ridicule from the criminals because of your calling to Allah or holding to the religion of Allah, know that you have a reward for it because it is in the path of Allah. Yes.