Does "whoever does not judge by what Allah has revealed" (Qur'an 5:45) only apply to judges (qadi)?

Question

Indeed, We sent down the Torah, in which was guidance and light. The prophets who submitted [to Allah ] judged by it for the Jews, as did the rabbis and scholars by that with which they were entrusted of the Scripture of Allah, and they were witnesses thereto. So do not fear the people but fear Me, and do not exchange My verses for a small price. And whoever does not judge by what Allah has revealed - then it is those who are the disbelievers. And We ordained for them therein a life for a life, an eye for an eye, a nose for a nose, an ear for an ear, a tooth for a tooth, and for wounds is legal retribution. But whoever gives [up his right as] charity, it is an expiation for him. And whoever does not judge by what Allah has revealed - then it is those who are the wrongdoers.
_{Qur'an 5:44-45}

I'm wondering who this applies to specifically. As far as I'm aware, qisas punishment goes through a Sharia court. So, I would expect it's not your average Joe Muslim who is "judging" in this verse, but rather judges or qadi, or people who are qualified to judge in some way.

However, this might also be interpreted as meaning a kind of "personal judgment", such as a belief that "a life for a life", etc., is fair and just, as ordained by Allah.

Question: Does "whoever does not judge by what Allah has revealed" only apply to judges (qadi)?

I found this tafsir:

... whoever does not show what the Qur'an has shown nor act according to it: (such are wrong-doers) who harm themselves with punishment.
_{Tanwîr al-Miqbâs min Tafsîr Ibn ‘Abbâs}

This suggests that qisas might be the "tip of the iceberg", referring to judging by all Muslims in all ways. It's not too clear to me, though.

Answer 1

One may answer this by logic in the following way:

If we accept and believe that Allah is just, then his shari'a is just so seeking an award outside of Allah's rulings must be a kind of injustice and denial of Allah's justice and shari'a which implicates that this is kufr (rejecting the truth)!

So basically there's no difference between a judge who instead of judging based on shari'a -which is known to him- renders a verdict which is not conform to the shari'a or a civil person who seeks his justice by willingly going to a court which does not render verdicts which are shari'a conform. Both have sinned in a bad way -by practicing injustice- which is (set) equal to kufr. The tafsirs who addressed this last part of verse 5:45 considered people who refer to other than the shari'a in their judgement as unjust or fassiq. Also they explain the verses that actually Jews (whom were meant in this context) knew the truth -the shari'a rulings- but didn't follow them to some extent.
Maybe an important addition comes from at-Tahrir wa-Tanwir which make clear that forgiving one an other doesn't count as such wrongdoing, but is a desirable behaviour. But the point of these verses is going against the total elimination of the right of qissas.

See also islamqa #974

Answer 2

No, it applies to everyone and all aspects of life.

But we have to remember that a principle in our religion is Balance;

If we can't do a certain obligated act, we do the next best thing that is within our capability that will not take up our whole day etc.

Sometimes there is more reward in abstaining from an obligatory act, e.g. not fasting in ramadan while feeling really sick