What is the ruling on saying "Ya 'Abdahu" (O his servant) to someone whose name is 'Abd al-Rahim?

The questioner : Please go ahead. The questioner says her husband's name is 'Abd al-Rahim. She calls him "Abdahu." Is that permissible, O Shaykh?

The Shaykh : "Abd" — who does the pronoun refer to? It refers to 'Abd al-Rahim. She says her husband's name is 'Abd al-Rahim, so she calls him and says, "Come, O Abdahu."

The questioner : No, we say, "Come, O 'Abd al-Rahim," or else, "O 'Abd," saying "Abd" without a pronoun: "Come, O 'Abd."

The Shaykh : And do not say, "Come, O Abu So-and-so," because the word "Abdahu" is only used with the pronoun. Do I make myself clear?
That is, perhaps a polytheist would say it, intending by "Abdahu" the servant of the idol he worships. Similarly, some people say "in his name" when they mean to say "in the name of Allah." This is wrong; rather, one should say "in the name of Allah," because we do not know what the one saying "in his name" intends by the reference of the pronoun. He may be among those who sanctify the awliya (close friends of Allah) and means "in the name of that wali."
A person must conduct himself with the etiquette established in the Book and the Sunnah. What came in the Book and the Sunnah is "Bismillah al-Rahman al-Rahim" (In the name of Allah, the Most Merciful, the Bestower of Mercy). Even the previous prophets would write "Bismillah al-Rahman al-Rahim," as in the story of the Queen of Saba, when a letter from Sulayman (Solomon) came to her,