What is the law for kissing the hands of rulers or scholars or parents? What is the law for kissing the hands of the Messenger of God (peace be upon him and his family) and the Imams of Ahl al-Bayt (peace be upon them), especially his Excellency Mahdi (peace be upon him)?
Kissing nobody’s hand is Sunnah, but kissing the hand of the Messenger of God, peace be upon him and his family, and His Caliph’s hand for blessing is permissible; As some of our helpers informed us and said: «أَرادَ رَجُلٌ أَن یُقَبِّلَ یَدَ الْمَنْصُورِ فَأَبْعَدَ یَدَهُ وَ قالَ لَهُ: أَ تُریدُ أَنْ تُغِرَّنِي کَما تُغِرُّ هَؤُلَاءِ الدَّجاجِلَةَ؟! لا یُقَبِّلُ الرَّجُلُ یَدَ الرَّجُلِ إلّا أَن یَکُونَ إِماماً مُفْتَرَضَ الطّاعَةِ! قالَ الرَّجُلُ: وَاللّهِ ما فَعَلْتُ ذَلِكَ إلّا لِأَعْلَمَ أَهُوَ مِنَ الدَّجاجِلَةِ أَمْ لا، فَعَلِمْتُ أَنَّهُ لَیْسَ مِنْهُمْ»; “A man wanted to kiss Mansoor’s hand, so he moved his hand away and said to him: Do you want to deceive me just as you deceive these Dajjals?! Nobody kisses nobody’s hand unless he is an Imam to whom obedience is obligatory! (After that) The man said: I swear to God, I did not do that unless to know if he is also from Dajjals or not, so I realized he is not from them”! Nevertheless, kissing the hands of the parents, if they are Muslims, has no problem; as one of our companions informed us and said: «سَأَلْتُهُ عَنِ الرَّجُلِ یُقَبِّلُ یَدَ والِدَیْهِ، فَقالَ: لا بَأسَ بِهِ، أَما سَمِعْتَ قَولَهُ تَعَالَى: ﴿وَاخْفِضْ لَهُمَا جَنَاحَ الذُّلِّ مِنَ الرَّحْمَةِ﴾؟!»; “I asked his honor about a man kissing the hands of his parents, he said: it has no problem, have you not heard the word of God Almighty who says: 'And lower to both of them the humble wing of kindness'?!”, but kissing the hands of tyrants and scholars who follow them is forbidden; as one of our companions informed us and said: «سَمِعْتُ الْمَنْصُورَ یَقُولُ: مَنْ قَبَّلَ یَدَ ظالِمٍ یُظْهِرُ بِذَلِكَ وَلایَتَهُ فَکَأَنَّما قَبَّلَ اللّاتَ وَ الْعُزَّى»; “I heard Mansoor says: whoever kisses the hand of an oppressor to declare his friendship to him, it is like that he has kissed Lat and Uzza” and in the book “Return to Islam” it has been said that his honor refused to kiss an arrogant scholar’s hand.