Ibn Majah

Benefits and Issues:

➊
It is permissible to kiss the Black Stone (Hajar al-Aswad) during the circumambulation (tawaf) of the Ka'bah, but it is not allowed to push and shove for this purpose.
If it is easy to kiss it, then this is better; otherwise, one should touch the Black Stone with a stick or hand and then kiss it.
If even touching the Black Stone with a stick or hand is difficult, then one should simply gesture towards the Black Stone and move on.
In this case, one should not kiss one's hand.

➋
Hazrat Umar radi Allahu anhu mentioned this matter so that the issue of monotheism (tawhid) and following (the Sunnah) becomes clear.
The polytheists used to touch idols or objects associated with elders for the sake of seeking blessings, and they believed that by touching them, their needs could be fulfilled.
There should be no suspicion regarding Muslims touching the Black Stone that they are worshipping a stone; rather, they do so solely as an act of following the Sunnah.

➌
Other than the Black Stone, it is not appropriate to kiss any other part of the Ka'bah; therefore, one should avoid kissing the walls of the Ka'bah, the threshold of its door, or the enclosure of Maqam Ibrahim.

➍
It is also not appropriate to kiss the Yemeni Corner (Rukn Yamani); only touching it is Sunnah.
During tawaf, if it is easy, one should touch the Yemeni Corner; otherwise, there is no need to gesture or anything similar—simply move on.

Hadith Commentary: Benefits and Issues: From this statement of Umar radi Allahu anhu, it is established that the conduct of a Muslim should be such that he follows and imitates the actions of the Messenger of Allah sallallahu alayhi wa sallam, whether or not he understands the wisdom and philosophy behind that action. Since the Prophet sallallahu alayhi wa sallam kissed the Black Stone (Hajar al-Aswad), we also kiss it. He touched the Yemeni Corner (Rukn Yamani) but did not kiss it; therefore, it is only touched and not kissed. However, to use the kissing of the Black Stone as evidence for the permissibility of kissing the hands and feet of pious and revered people is not correct. If this act were correct, then the Companions radi Allahu anhum ajma'in would have kissed the hands and feet of the Messenger of Allah sallallahu alayhi wa sallam at every meeting, and this action of the Companions radi Allahu anhum ajma'in would have been established by both verbal and practical mass transmission (tawatur qawli and tawatur amali). Furthermore, to use this as evidence for inherent and bestowed power is also misplaced.

Because if Allah Ta'ala has placed some benefit in a thing, it does not mean that the capacity for benefit has been granted to it. For example, if believing in the Messenger of Allah sallallahu alayhi wa sallam, loving him, and obeying him becomes a cause for entering Paradise, how does this mean that the ability to grant benefit has been given to his person? Therefore, how astonishing is this argument! Who can deny the benefit of the Messenger of Allah sallallahu alayhi wa sallam, that if a person says "Muhammad, the Messenger of Allah sallallahu alayhi wa sallam," he becomes deserving of Paradise? In fact, until a person says "Muhammad, the Messenger of Allah sallallahu alayhi wa sallam," he will not be deserving of entering Paradise. Allahu Akbar! If this is the state of benefit in his name, then what must be the state of benefit in his person! And I say that whoever denies the benefit of the Messenger of Allah sallallahu alayhi wa sallam should not mention his name and should show us by entering Paradise.

(Sharh Sahih Muslim, Saeedi, vol. 3, p. 501)

Someone should ask this servant of Allah: Is entry into Paradise the result of faith in the Prophethood of the Messenger of Allah sallallahu alayhi wa sallam, or is merely mentioning his name the cause of entering Paradise? If a person recites the tasbih of your name a thousand times a day, but does not believe in you, will he be able to enter Paradise? (Abu Talib supported you sallallahu alayhi wa sallam at every difficult and trying moment, served you in every way, yet he could not enter Paradise, and this is also acknowledged by you sallallahu alayhi wa sallam. (Sahih Muslim, vol. 1, p. 835.))

In any case, this division between inherent and bestowed (dhati and ata'i) is nothing but a mirage with which the ignorant and the unaware are deceived.