Is al-Muqsit (the Most Just) one of the names of Allah?
Question

Is al-Muqsit (the Most Just) one of the names of Allah? Please give evidence from the Quran and Sunnah.
Praise be to Allah.A number of scholars regard al-Muqsit (the Most Just) as one of the names of Allah. The evidence for that – in their view – is the verse (interpretation of the meaning): {And We place the scales of justice [al-qist] for the Day of Resurrection} [al-Anbiya’ 21:47].
It was narrated that Abu Musa (may Allah be pleased with him) said: The Messenger of Allah (blessings and peace of Allah be upon him) stood and told us four things: “Allah does not sleep and it is not befitting that He should sleep; He raises the Balance and lowers it…” (Narrated by Muslim, al-Iman, 1/112).
Those who narrated it include:
It was narrated via ‘Abd al-Malik ibn Muhammad as-San`ani and others, including:

al-Khattabi 2. Ibn Mandah 3. Al-Halimi 4. Al-Bayhaqi 5. Al-Asbahani 6. Ibn al-‘Arabi 7. Al-Qurtubi 8. Ibn al-Qayyim 9. Ash-Sharbasi 10. Nur al-Hasan Khan.

(Mu`taqad Ahl as-Sunnah wal-Jama`ah fi Asma’ Allah al-Husna by Muhammad Khalifah at-Tamimi, 251).
The author thought it most likely that it is not one of the names of Allah, because it is not mentioned in the Quran as one of His names.
Among the contemporary scholars who listed it as one of the beautiful names of Allah was Shaykh Salih Al ash-Shaykh (may Allah preserve him), who said:
[They also quoted as evidence] the verse (interpretation of the meaning): {and act justly [aqsitu]. Indeed, Allah loves those who act justly} [al-Hujurat 49:9].
{act justly [aqsitu]} means: Be fair. It is a verb that comes from the root aqsata; the active participle of this verb is muqsit, meaning one who is just. This is in contrast to the verbal root qasata [meaning to act wrongfully], of which the active participle is qasit (pl. qasitun), which refers to those who do wrong and transgress, as in the verse {But as for the unjust [al-qasitun], they will be, for Hell, firewood} [al-Jinn 72:14].
As for the word al-Muqsit, it is one of the names of Allah, may He be glorified and exalted, for He is al-`Adil (the Just) Whose justice is perfect; it is more emphatic in meaning than the name al-`Adil.
Hence al-`Adil is not one of the names of Allah; rather al-Musqit is one of His names. One of the attributes of Allah, may He be glorified and exalted, is that He is al-Hakm al-‘Adl (the just Judge); al-`A dl means that He is the possessor of justice, and al-Muqsit is more emphatic in meaning than al-`Adl, because iqsat is `adl (justice) and more. (End quote from Sharh al-`Aqidah al-Wasitah, 1/211)
What it means – assuming that it is proven to be one of the divine names – is: the One Who is just in His judgement, and does not wrong anyone or treat anyone unfairly, for He, may He be glorified, is the One Who deals with His slaves on the basis of justice (al-`adl). Or it may mean that He is the One Who gives each person a share (qist) of His bounty.
(Ifrad Ahadith Asma’ Allahi wa Sifatihi, 1/135).
For more information, please see the answers to questions no. 84270 .
And Allah knows best.