A word by Shaykh Al-Albani on the meaning of the hadith: (So blessed are the strangers)

The Shaykh: for them, as he (peace be upon him) said: , . "Tuba" has two interpretations, a linguistic one and a legal one. The linguistic one is "blessed are they," or in the colloquial Syrian expression: "may they attain it." These strangers, "may they attain it." As for the legal interpretation, which is the one that should be relied upon, because the Messenger (peace be upon him) interpreted it himself when he said in some authentic hadiths: . meaning: under the shade of its branches for a hundred years without reaching the end. So this tree is for the strangers. The Messenger of Allah (peace and blessings be upon him) gave them good tidings of this good tree. In my opinion, just as it is important to know what is for these strangers, we must know, and this is more obligatory to know, who these strangers are? Because I fear that the matter is as the poet said:
"And every one claims a connection to Layla *** And Layla does not approve of that for them"
Some people may think that the strangers are those who hold fast to their religion, whether that religion is correct or deviant, and so on and so on. To dispel this kind of vague rambling that many people engage in in their research and statements, where they ask a question and say to you: "It may be such and such, or it may be such and such," giving you absolutely nothing with this vagueness, I think it is more obligatory to know these strangers whom the Master of the Prophets gave good tidings of having "tuba." And He (the Exalted) said: This is the tree; so who are these strangers?
There are three narrations describing them, and they do not contradict each other, as some may think, because these are meanings that may converge in one person or several, or may not converge. The first narration says: They said, "Who are they, O Messenger of Allah?" He said: . So one of the characteristics of these strangers, in a spiritual sense, is like those strangers in a material sense when a person migrates from his country to another country where no one knows him, and he is rejected and neglected among them. Similarly, the stranger described in this hadith with the characteristic of spiritual rejection, he said: .
There is no doubt that righteousness is of two types: one is intellectual, and the other is practical and moral. People, even good people, have become accustomed to focusing on the second aspect of being a stranger, which is righteous deeds and good character. But they never think that the best strangeness, and the one whose owner is most deserving of "tuba," is strangeness in creed. , in their creed, which is the foundation and the origin of the call, then in their morals, then in their deeds. So they are strangers in everything in that society. Therefore, they are opposed and disobeyed and not obeyed. This is the description in the first narration.
It is perhaps appropriate to mention here that for such strangers, the few righteous ones who live in a large and numerous society, . He (peace and blessings be upon him) said in some authentic hadiths that there will be people who are strangers in the last of time, and they have the reward of fifty. They said, "From us, O Messenger of Allah, or from them?" He said: ; they have the reward of fifty of the martyrs among the Companions of the Messenger (peace and blessings be upon him). And an explanation of this came in some hadiths, and this explanation feels to me like an explanation of the fewness, the cause of the fewness and the multitude. He said: . This is the ultimate strangeness.
The second hadith describing these strangers.

The questioner: Is there a martyr in it, or fifty?

The Shaykh: Fifty from you.

Another questioner: Is there a martyr?

The Shaykh: No, there is no martyr. In two hadiths: , and each of the two hadiths is weak in chain of narration. But the hadith I recited to you just now is an authentic hadith. They have the reward of fifty of the Companions.

The questioner: They do the same work as them. The one who works in it has the reward of fifty workers from you.

The Shaykh : Yes?

The questioner: The one who works in it has the reward of fifty workers from you.

The Shaykh: From you.
Yes.