Assalamualaikum ustaz. I heard that we cannot name our children names such as Yasar, Rabah and others. I’m confused because it has a good meaning. Yasar means ease and not difficult while Rabah means profit. Why?
Alhamdulillah, praise and gratitude to Allah SWT for His countless blessings for us all. Praise and salutations to our beloved Prophet Muhammad PBUH, his family, companions and all those who follow his footsteps until the Last Day.
Among the uniqueness of a human is that each has its own name. This is unlike other creatures which are only given a general name such as tree, animal, goat, cow and others.
The chosen name should be ones that are approved and loved by Allah SWT. This is what should be. Rasullullah PBUH said:
تَسَمَّوْا بأسماءِ الأنبياءِ، وأَحَبُّ الأسماءِ إلى اللهِ تعالى عبدُ اللهِ وعبدُ الرحمنِ، وأَصْدَقُها حارثٌ وهَمّامٌ، وأَقْبَحُها حَرْبٌ ومُرَّةٌ.
“Call yourselves by the names of the Prophets. The names dearest to Allah are Abdullah and AbdurRahman, the truest are Harith and Hammam, and the worst are Harb and Murrah.” 
Regarding the above question, there is certainly a hadith from Samurah bin Jundub, he said: The Messenger PBUH said:
لا تُسَمِّينَّ غُلامَكَ يَسارًا ولا رَباحًا ولا نَجيحًا، ولا أفلَحَ؛ فإنَّك تقولُ: أثَمَّ هو؟ فيقول: لا، إنَّما هنَّ أربَعٌ؛ فلا تَزيدُنَّ عَلَيَّ
“Do not call your servant Yasar (wealth), Rabah (profit), Nijih(prosperous) and Aflah (successful), for you may ask; Is he there? And someone says: No. Samurah said: These are four (names), so do not attribute more to me.”
Narrated by Muslim (2137) Abu Daud (4958) al-Tirmizi (2836) and Ahmad (20078)
Dr Aidh al-Qarni said: The meaning of this hadith is that when you named your child one of these names, for instance, you say, is Yasar (ease) home, and then it is answered: “No.” hence, it could lead to difficulty or adversity there. Or if you ask, Is Rabah (profit) home? And it is answered: “No,” then the place of Rabah (profit) will turn into a loss. Such is the same for others like it. 
This shows how Rasullullah PBUH took a tafa’ul approach in hoping for good and closing all the doors towards downfall, humiliation and negativity. This is the reason why such names aren’t encouraged although we found that some scholars or some people named their children with names as stated above.
May Allah grant us understanding in religion.
 Narrated by Abu Daud (4950) and al-Bukhari in al-Adab al-Mufrad (814)
 See Mulhim al-‘Alam, pg. 166-167