Praise be to Allah.
It is not permissible to swear an oath except by Allah or by one of His names or His attributes, because of the reports narrated by al-Bukhaari (2679) from ‘Abdullah ibn ‘Umar (may Allah be pleased with him), that the Prophet (blessings and peace of Allah be upon him) said: “Whoever swears an oath, let him swear by Allah or remain silent.”
The aayaat of Allah are of two types:
The aayaat shar‘iyyah (revealed verses), which are the words of Allah, may He be exalted, in the Qur’an and elsewhere, which He revealed to His slaves or spoke.
The aayaat kawniyyah (universal signs), such as night and day, the heavens and the earth, which point to His greatness, His knowledge and His wisdom.
Based on that, if someone swears by the aayaat of Allah, there must be one of two scenarios:
The first scenario is when he swears by the aayaat of Allah, and what he means by the aayaat are the words of Allah, such as the Holy Qur’an. Swearing such an oath in this case is permissible, because the Qur’an is the word of Allah, and His word is one of His attributes.
The second scenario is when he swears by the aayaat of Allah, and what he means by the aayaat is the aayaat kawniyyah, such as night and day, or the sun and the moon. Swearing such an oath in this case is not permissible, because the aayaat kawniyyah are created, and swearing by something that is created is not permissible.
The scholars of the Permanent Committee were asked: What is the ruling on swearing by the aayaat of Allah, and saying: “I swear by the aayaat of Allah”?
They replied: It is permissible to swear by the aayaat of Allah if the one who is swearing the oath intends to swear by the Qur’an, because it is the word of Allah, and His word is one of His attributes, may He be glorified. But if he means something other than the Qur’an when he swears by the aayaat of Allah, that is not permissible.
And Allah is the source of strength. May Allah send blessings and peace upon our Prophet Muhammad and his family and companions.
Bakr ibn ‘Abdillah Abu Zayd (member), Saalih ibn Fawzaan al-Fawzaan (member), ‘Abd al-‘Azeez ibn ‘Abdillah Aal ash-Shaykh (president)." (Fataawa al-Lajnah ad-Daa’imah – Vol. 1 23/48).
Shaykh ‘Abd ar-Rahmaan al-Barraak (may Allah preserve him) said: It is permissible to swear by the word of Allah or by the words of Allah, and also to swear by the aayaat of Allah, if what is meant is the aayaat (verses) of the Qur’an, such as if someone says: By the revealed aayaat of Allah, or By the aayaat of the Qur’an. As for the created aayaat (signs), such as the sun and moon, it is not permissible to swear by them, because it is not permissible to swear by created things. So whoever intends when he says “By the aayaat of Allah” to refer to the created aayaat has sworn by something other than Allah, and swearing by anything other than Allah is shirk, as it says in the hadith: “Whoever swears by anything other than Allah has disbelieved or has associated something else with Allah (shirk).” Narrated by Ahmad, and by at-Tirmidhi who classed it as hasan; classed as saheeh by al-Haakim. In most cases, the one who says, “By the aayaat of Allah” is referring to the aayaat (verses) of the Qur’an, so his oath is permissible. End quote.
And Allah knows best.