Islam places importance on choosing good names with sound meanings, as names carry meanings and identity. The Prophet ﷺ would sometimes change names that had inappropriate, negative, or problematic meanings. It is reported that he ﷺ changed certain names, including “Shihāb,” in specific instances.

The word “Shihāb” in Arabic means a flame, a shooting star, or a blazing fire. It appears in the Qur’an in a neutral or descriptive sense, such as: “Except one who snatches a hearing, and is pursued by a clear burning flame (shihāb).” (15:18). Because of this meaning, some scholars mentioned that the Prophet ﷺ changed this name in a particular case due to its connotation of fire or harshness.

However, the key point is that the Prophet ﷺ did not issue a general prohibition of the name “Shihāb” for the entire Ummah. Rather, like many names he changed, it was done in specific cases where a better name was preferred. For this reason, the majority of scholars consider the name “Shihāb” to be permissible, though not necessarily among the most recommended names.

Therefore, it is permissible to keep the name “Shihāb,” and there is no sin upon your friend for having it. If someone wishes to change it to a name with a more positive or clearly praiseworthy meaning, such as names including ʿAbdullāh, ʿAbd al-Raḥmān, or names of the Prophets, that would be commendable, but it is not required.

As for the name “Āshikur Raḥmān,” this requires more caution. The word “ʿĀshiq” (often pronounced “Āshik”) means “lover” in an intense or passionate sense. While “al-Raḥmān” is one of the Names of Allah, combining it in this form, “lover of al-Raḥmān,” is not from the established naming patterns in the Sunnah. The most appropriate and established form is using “ʿAbd,” such as ʿAbd al-Raḥmān (servant of the Most Merciful), which the Prophet ﷺ praised.

Scholars generally recommend avoiding names that combine Allah’s Names in unconventional or linguistically awkward ways, especially when they may carry ambiguous meanings. Therefore, “Āshikur Raḥmān” is not considered an ideal Islamic name. It would be better to use names that are clearly established and sound in meaning, such as ʿAbd al-Raḥmān.

In summary, the name “Shihāb” is permissible and does not need to be changed, though choosing a more virtuous name is always better. The name “Āshikur Raḥmān” is not preferred, and it would be advisable to use more established and appropriate Islamic names.