The allegation of the non Ahmadi Muslims is that all prophets have to be from the lineage of Ibrahim(as) and try to claim that Ahmad(as) is not from there. The non Ahmadi Muslims quote this ayah:
And We bestowed on him Isaac and Jacob, and We placed the gift ofprophethood and the Book among his descendants, and We gave him his reward in this life, and in the Hereafter he will surely be among the righteous.(Chapter 29 Verse 28)
This allegation has many answers. The first one is that Ahmad(as) is from the Persian Lineage which is from Banu Ishaaq so Ahmad(as) is indeed from the same descendants as mentioned in the ayah.
Allah also States:
And remember when Abraham said, ‘My Lord, make this city a city of peace, and keep me and my children away from worshipping idols.‘My Lord, they have indeed led astray many among mankind. So whoever follows me, he is certainly of me; and whoever disobeys me — Thou art, surely, Most Forgiving, Merciful(Chapter 14 Verses 36-37)
Hazrat Ibrahim(as) has made it clear that one who follows him is certainly of him. Ahmad(as) was indeed a true follower of every prophet before him.
Another answer to this is that in Surah Hajj Allah has Stated:
“And strive in the cause of Allah as it behoves you to strive for it. He has chosen you, and has laid no hardship upon you in religion; so follow the faith of your father Abraham; He named you Muslims both before and in this Book, so that the Messenger may be a witness over you, and that you may be witnesses over mankind. Therefore observe Prayer and pay the Zakat, and hold fast to Allah. He is your Master. An excellent Master and an excellent Helper!” (Chapter 22 Verse 79)
Ibrahim(as) here has been called our father. This does not mean that he is our physical father, rather a spiritual father. Ibrahim(as) is a spiritual father of the true Muslims. This is similar to the Ayah of the Qur’an where Allah states:
The Prophet is nearer to the believers than their own selves, and his wives areas mothers to them. And blood relations are nearer to one another, according to the Book of Allah, than the rest of the believers from among the Helpers as well as the Emigrants, except that you show kindness to your friends. Thatalso is written down in the Book.(Chapter 33 Verse 7)
Here Allah has called the wives of the Prophets the Mothers of the believers. This also does not make them physical mothers of the believers, rather spiritual mothers.
However, Ahmad(as) was from the Persian lineage as well of the Farsi who are from Banu Ishaaq which is why he is included in the physical lineage as well.
It is written in Kanzul Ummal which is a well known book of Ahadith in regards to The Persians and clearly states they are from these descendants:
It is also written: