Lexists however employ the same when they would like to...
And He Alone is the Extremely Exalted & Great Forever [^68] In our present situation our vocative and addressee is Imam al-Hussein ('a) who due to his freedom from the limitations of the material world and comprehensive being is too close to us and can see and hear us too. Hence the reason why we employ the interjection 'ya and say 'Ya Aba 'Abdillah' is to express his exaltedness and confess our lowliness.
The people of heart, however, can well appreciate the implication manifested when the 'the lover calls the beloved'. The implication is to get near to the Beloved. Hence when we call Aba 'Abdillah (whose import, as we shall soon expound means 'the utterly submissive slave of Allah) we are seeking his closeness, or in other words 'the attributes that personifies his exalted being'.
اَبَا عَبْدِ اللهِ Aba 'Abdillah The words Aba 'Abdillah literally mean 'the father of the submissive slave of Allah'. Arabs honorify their fellow brothers by calling them with a kunya (a name that mostly mentions the first or one of the offsprings of the 'named one'.) Hence if a person had a son called 'Abdullah, he is called Abu 'Abdillah, which means 'father of 'Abdullah'.
In fact one of our traditions indicates that it is better to call someone by his offspring's name in front of him than to use his real name. Imam al-Riza ('a) is reported to have said: إذَا ذَكَرْتَ الرَّجُلَ وَهُوَ حَاضِرٌ فَكَنِّهِ وَإِذَا كَانَ غائباً فسَمِّهِ.
If you mention a man in his presence, then do so using his agnomen (kunya), and if he were to be absent, then call him by his name.[^69] One of the variable reasons given behind the Imam ('a) being called Abu 'Abdillah is that he had an offpring called 'Abdullah, famously known الرضيع al-radi' (one who is still breastfeeding). He is one of the members of the Imam's noble family who was mercilessly martyred in the plains of Karbala.