Is it permissible to ask about the form of Jibreel (upon him be peace) and why he was named Ar-Ruh Al-Amin (The Trustworthy Spirit)?

It is permissible for a Muslim to inquire about the attributes of angels for the purpose of learning and enlightenment. Among the attributes of Jibreel (Gabriel), peace be upon him, mentioned in the Holy Qur'an are: "strong in power, having a sound constitution," and "Indeed, it is the word of a noble messenger. Possessor of power, eminent with the Lord of the Throne. Obeyed there and trustworthy." The Prophet, peace and blessings be upon him, saw Jibreel in his true form, in which he was created, and he filled the horizon, and he had six hundred wings.

As for the reason he is called "Ar-Ruh Al-Amin" (The Trustworthy Spirit), it is said he is called "Ruh" (Spirit) because souls are revived by him just as they are revived by spirits, or because he was created from spirit, or because he is the salvation of creation in religion, or because he is entirely spirit. He is called "Amin" (Trustworthy) because he is entrusted with what he conveys to the prophets and others, and because he is trustworthy over the revelation of Allah.