In The Name of Allaah, The Most Merciful, The Bestower of Mercy.
The Angels were created from light and the (origin) of the children of Aadam is clay; however Sound Aqeedah creates a bond between these two creatures- Angels and the pious people amongst the children of Aadam. Allaah (The Most High) said:
ٱلَّذِينَ يَحۡمِلُونَ ٱلۡعَرۡشَ وَمَنۡ حَوۡلَهُ ۥ يُسَبِّحُونَ بِحَمۡدِ رَبِّہِمۡ وَيُؤۡمِنُونَ بِهِۦ وَيَسۡتَغۡفِرُونَ لِلَّذِينَ ءَامَنُواْ رَبَّنَا وَسِعۡتَ ڪُلَّ شَىۡءٍ۬ رَّحۡمَةً۬ وَعِلۡمً۬ا فَٱغۡفِرۡ لِلَّذِينَ تَابُواْ وَٱتَّبَعُواْ سَبِيلَكَ وَقِهِمۡ عَذَابَ ٱلۡجَحِيمِ
Those (angels) who bear the Throne (of Allaah) and those around it glorify the praises of their Lord, and believe in Him, and ask forgiveness for those who believe (in the Oneness of Allaah) (saying): ‘’Our Lord! You comprehend all things in mercy and knowledge, so forgive those who repent and follow Your way, and save them from the torment of the blazing fire.’’ [40:7]
The angels believe in Allaah and constantly supplicate to Allaah. They ask Allaah to forgive the believers and to enter them into paradise. This is a great and amazing bond despite the fact that they (angels) are a different from humans, however it is the sound Aqeedah that unites their hearts.  Likewise, the righteous slaves of Allaah amongst human beings love the angels. 
 Source: Al-Madkhal Li- Diraasatil Aqeedatil Islaamiyyah, lesson number 3’ by Shaikh Abdur-Razzaaq Al-Badr (may Allaah preserve him)
 Source: Explanation of the forty hadeeth of Imaam An-Nawawi’ lesson 12’ by Shaikh Abdur-Razzaaq Al-Badr (may Allaah preserve him)