First interpretation of this Hadith
In regard to this Hadith, the Hadith-Masters have given an opinion that the “city of Caesar” mentioned in the Hadith is not Constantinople, but Hims, which was the capital of Roman Empire in the days of the Prophet (Peace Be upon Him ). This city is presently in Syria & is called “Homs”.
It is given in Fath Ul Bari in the interpretation of this Hadith.
Translation: Some interpreters have said that the city of Caesar means the city which was the capital of the Roman Empire in the blessed era of the Holy Prophet (Peace Be upon Him ). That city is Hims. At that time, it was the capital of the Roman Empire. (Fath Ul Bari, Kitab Ul Jihad).
This interpretation is all the more significant, because in Sahih Bukhari & in all other books, the word “Constantinople” is not used. Only “the city of Caesar” is mentioned. Caesar was the Emperor of the Roman Empire. The city in which he lived or was his capital will only be termed as “city of Caesar.” According to the wording of the Hadith, that city is Hims. In the caliphate of Hadhrath ‘Umar Al Farooq (May Almighty-Allah be well pleased with him), in 15 Hijri, an army under the comm& of Hadhrath Abu ‘Ubaidah bin Jarrah (May Almighty-Allah be well pleased with him) attacked Hims. Muslims laid
siege to Hims in harsh winter & the end of winter, they conquered it. In this battle, Hadhrath Khalid bin Walid (May Almighty-Allah be well pleased with him), Hadhrath Bilal (May Almighty-Allah be well pleased with him), Hadhrath Miqdaad (May Almighty-Allah be well pleased with him) & many other Companions participated.
ImaamIbn Atheer (May Almighty-Allah shower His mercy on him) has mentioned among the incidents of 15 Hijri, in Tarikh Kamil, Volume. 2, Page No. 339:
Translation: When Hadhrath Abu ‘Ubaidah bin Jarrah (May Almighty-Allah be well pleased with him) finished the campaign of Damascus, he took the route of Ba’albak to Hims.
At that time Yazid was not even born, let alone participating in the battle. Yazid was born in 26 Hijri as ImaamIbn Atheer (May Almighty-Allah shower His mercy on him) wrote in Bidayah wan Nihayah, Volume. 9, Page No. 76.
Translation: Yazid bin Mu‘awiyah was born in 26 Hijri.
A possible objection against this Hadith might be that in the Hadith mentioned, first the Jihad by sea is mentioned, in which Hadhrath Umme Haraam (May Almighty-Allah be well pleased with her) is a participant, then the siege of the city of Caesar is mentioned. If the city of Caesar is Hims, then it should have been mentioned first but it is not so.
The Holy-Prophet (Peace be upon Him) first mentioned the Jihad by sea & then the siege of the city of Caesar. It should be remembered that the order of incidents might be according to what is being said or might be according to the order of occurrence. In this Hadith, it is according to what is said, not in the order of occurrence.
Second interpretation of this Hadith
Other interpreters have opined that “the city of Caesar” means Constantinople. Still Yazid is not included in the ambit of the said Hadith as Muslims attacked Constantinople a number of times & the glad tidings of forgiveness are only for those who participated in the first siege.
Now, what is to be seen is that, when did Muslims attack Constantinople for the first time & which is the first army?