Some people say that to kiss the hands and the feet of the pious people are prohibited and Shirk (associating partners with Allah). They say that by bending (like in Ruku) and kissing the feet of the pious we are making Sajdah to a creation of Allah Ta’ala.

The Ahl as-Sunnah w'al Jama'ah believes that this act is permissible and desirable as the books of Ahadith prove that the Ahl al-Bayt and the Sahaba-e-Ikraam kissed the blessed hands and feet of the Most Beloved  Prophet (Salla allahu Ta'ala 'alayhi wa sallam) and they even kissed the hands and the feet of one another.

The word Sajdah in the Shari’h is meant that while doing Sajdah eight parts of the human body must touch the ground, namely both feet (toes), both the knees, both the arms (hands), nose and the forehead, with the express intention (Niyah) of doing Sajdah.Without the clear intention of Sajdah if a person lies on the ground by bending his legs and feet (as is usually done when some one feels extreme cold or he is inflicted with some ailment), this will not mean Sajdah. Therefore, to kiss the feet of the elders or pious persons is not Sajdah since it does not satisfy the conditions of Sajdah.

Sajdah is of two kinds:
(a)  Sajdah Tahiyah (by way of greeting) is when a person meets some dignitary,then to express his reverence the one meeting the dignitary touches the ground with his forehead, while the Sajdah is to regard some one as a deity or god.
(b)  Sajdah Ibaadah (worship) is Haraam in every Shari’ah.

Sajdah Tahiyat was permissible from the time of Hadrat Adam (alayhis salaam) to the Most Beloved Prophet (Salla allahu Ta'ala 'alayhi wa sallam). The Angels offered Sajdah before Hadrat Adam (alayhis salaam). Hadrat Yaqub (alayhis salaam) and the brothers of Hadrat Yusuf (alayhis salaam) offered Sajdah to Hadrat Yusuf  (alayhis salaam). Later on, this Sajdah Tahiyah was declared as Haraam in the Shari’ah of Islam as well. Any one doing Sajdah-e-Tahiyah is guilty of a sin and committing act of Haraam. But he is not a Mushrik or a Kaafir. He can offer repentance (Taubah) in the presence of Allah.

As far as the question of bending before someone is concerned, this bending is of two kinds. If it is by way of respect to anyone, provided it is not to the extent of bending as in Ruku. If it is so then it is Haraam and Islamic Jurists have forbidden this kind of bending. The other kind of bending is while doing some other work such as picking the shoes with a spirit of respect.This latter posture is permissible (Halaal) as it has notinge of worship.

When the Most Beloved Prophet Muhammad (Salla allahu Ta'ala 'alayhi wa sallam) visited the house of his daughter, Hadrat Fathima Zahra (radi Allahu ta'ala anha) she would stand up for him in respect, take his hand and kiss it and make him sit in her place. When Hadrat Fathima Zahra (radi Allahu ta'ala anha) visited the Most Beloved Prophet (Salla allahu Ta'ala 'alayhi wa sallam), then he would stand up for her, hold her hand and kiss it and allow her to sit in his place. (Abu Dawood; Mishkaat Shareef)

Hadrat Abdullah ibn Umar (radi Allahu ta'ala anhu) says that the Sahaba-e-Ikiram kissed the blessed hands of the Most Beloved Prophet (Salla allahu Ta'ala 'alayhi wa sallam). (Abu Dawood)

Hadrat Ashbah (radi Allahu anhu) went to the court of the Most Beloved Prophet (Salla allahu Ta'ala 'alayhi wa sallam), held the hand of the Noble Prophet (Salla allahu Ta'ala 'alayhi wa sallam) and kissed it. The Beloved Prophet (Salla allahu Ta'ala 'alayhi wa sallam) said,"In you there are two habits which is dear to Almighty Allah and the Noble Prophet (Salla allahu Ta'ala 'alayhi wa sallam)" (Adabul Mufrad) From this incident it is clear that the kissing of the hands is a desired action, which was even preferred by the Beloved Prophet Muhammad (Salla allahu Ta'ala 'alayhi wa sallam).

Once, two Jews came to the Most Beloved Prophet (Salla allahu Ta'ala 'alayhi wa sallam) and asked him a question. The Noble Prophet (Salla allahu Ta'ala 'alayhi wa sallam) answered them. Thereafter, they kissed the hands and the feet of the Beloved Prophet (Salla allahu ta'ala 'alayhi wa sallam) and told him that they bear testimony that he is a Nabi. (Tirmidhi Shareef; Mishkaat Shareef)

A man came to the Most Beloved Prophet (Salla allahu Ta'ala 'alayhi wa sallam) and told him that he had taken a vow that should Allah Ta'ala grant Rasoolullah (Salla allahu Ta'ala 'alayhi wa sallam) victory over Makkah, he would go the Beloved Kaaba and kiss the chaukat. The Noble Prophet (Salla allahu Ta'ala 'alayhi wa sallam) instructed him:'Go and kiss the feet of your mother.Your vow will be complete' (Umdatul Qaari)

Imam al-Ghazzali (radi Allahu ta'ala anhu) states that Hadrat Abu Ubaidah bin Jarrah (radi Allahu ta'ala anhu) kissed the hand of Hadrat Umar Farouk (radi Allahu ta'ala anhu). (Kimya-e Sa'adat; Awaariful Mu'aarif)

Whenever the Sahaba-e-Ikraam would return from a journey they would embrace one another and kiss the hands of one another. (Bustaanul Arifeen)

It is said in "Alamgiri", Bab Mulaqatul Muluk, that if someone kisses the hand of a learned Scholar or the just King because of his erudition (learning) and the quality of justice with his people then there is no harm in it.

In the same book "Alamgiri", Bab Ziyaratil Qubur, it is said that it does not matter much if some one  kisses the graves of his parents.

There are five kinds of kisses:

(a)  the kiss of affection and love like a father kissing his son,

(b)  the kiss of meeting (mulaqat) like a Muslim kissing another Muslim on meeting one another,

(c)  the kiss of love and regard like a son kissing his parents,

(d)  the kiss of friendship, when some one kisses his friend, and

(e)  the kiss of sensual love, like the husband kissing his wife or vice versa.

Some have added another kind of kiss as a mark of religious sanctity like of the Hajar-e-Aswad.(Alamgiri)

There is another kiss and it is in respect of religious sanctity and it is the kissing of Hajar-e-Aswad and the threshold of the Blessed Kaaba. Some have said that kissing the Qur'an al-kareem is Bid’ah. However, it is reported that Hadrat Umar (radi Allahu Ta'ala anhu) used to kiss the Noble Qur'an al-kareem every
morning by holding it in his hands. Kissing the bread (roti) is permissible before Imam Shafa’ee (radi Allahu ta'ala anhu) as a permissible Bid’ah or Bid’at-e-Hasanah. (Durre Mukhtar)

It is now obvious that to kiss the hands and feet of the pious and respected persons is Sunnah and those who regard this Shirk and a Bid'at have no basis in their arguments.