Hadees Related to Parents (Waldain)

Jabir Radiyallahu 'anhu narrates that Rasulullah Sallallahu 'alaihi wasallam said: Anyone with these three qualities shall be under the shade of Allah's Mercy (on the Day of Resurrection) and will be admitted into Paradise: 
(1) Courtesy towards the weak 
(2) Compassion to parents 
(3) Kindness to slaves (subordinates). (Tirmidhi)

Hadees Related to Slaves (Ghulam)

Abu Umamah Radiyallahu 'anhu narrates that Nabi Sallallahu 'alaihi wasallam returned from Khyber and with him were two slaves. So, 'Ali Radiyallahu 'anhu said: O Rasulallah! Grant us a servant. He replied: Take anyone you desire of the two. 'Ali said:
Choose for me. Rasulullah pointing to one said: Take him, but do not beat him; for I saw him offering Salat on our return from Khyber, and I have been forbidden to beat those who perform Salat. (Musnad
Alimad, Tabarani, Majma'uz-Zawaid)

Hadees Related to Namaz (Salat) And Slaves

'Ali Radiyallahu 'anhu narrates that the last words of Rasulullah Sallallahu 'alaihi wasallam were: As-Salat, as-Salat; fear ALLAH about those whom your right hand possesses (your slaves and subordinates). (Abu Dawud)
Note: ' Vigilantly observe, guard and establish Salat.