The faith of the Prophets increases but never decreases because they continually grow in knowledge, certainty, and recognition of Allah. However, they are protected from doubt and disbelief. Abraham's (peace be upon him) request was not due to any doubt about the resurrection; rather, he wished to move from the certainty gained through knowledge to the certainty gained through direct observation. Likewise, the Prophet's ﷺ statement, "We have more right to doubt than Abraham," is not an affirmation that Abraham doubted. Instead, it is a powerful way of denying that any doubt existed in either Abraham or the Prophet ﷺ.
Yes.
The faith of the Prophets increases through greater knowledge, deeper certainty, and a more profound awareness of Allah, as well as through witnessing His signs, revelation, and support.
For this reason, the scholars have affirmed that the Prophets possess the most complete faith of all people. Their faith increases in degrees of perfection and certainty, but it never decreases because Allah has protected them and kept them steadfast upon the truth.
No.
Abraham (peace be upon him) never doubted Allah's power to bring the dead back to life.
When Allah asked him, he replied:
"Yes indeed, but only so that my heart may be at ease."
(Qur'an 2:260)
In other words, Abraham was already certain of Allah's power. He simply wished to move from certainty based on knowledge to certainty through direct witnessing, because seeing something with one's own eyes brings a deeper sense of reassurance than merely knowing it.
For this reason, scholars have said:
"Hearing about something is not like seeing it."
Certainty of knowledge ('Ilm al-Yaqin) means knowing something with absolute conviction through truthful information.
Certainty of direct observation ('Ayn al-Yaqin) means personally witnessing it.
Abraham (peace be upon him) already believed in the resurrection with complete certainty, but he asked Allah to show him how the resurrection takes place so that his reassurance and certainty would become even greater.
The Prophet ﷺ said:
"We have more right to doubt than Abraham..."
This does not mean that Abraham doubted, nor does it mean that the Prophet ﷺ doubted.
Rather, the meaning is:
If it were even possible for Abraham to experience doubt, then I would have had a greater reason to do so. Yet I have no doubt whatsoever. Therefore, Abraham—who is even more deserving of certainty—certainly did not doubt either.
This is a well-known Arabic rhetorical style used to emphatically deny doubt altogether while highlighting the completeness of Abraham's certainty.
Yes.
The Prophets are protected from disbelief and from doubting what Allah has revealed to them. They are also protected in conveying Allah's message faithfully.
For this reason, Ahl al-Sunnah unanimously agree that Abraham (peace be upon him) never doubted the resurrection. Rather, he sought greater reassurance by witnessing the manner in which Allah gives life to the dead.
And Allah knows best.