Why is the legacy mentioned first in the aayah, “after payment of legacies that you may have bequeathed or debts” [al-Nisa’ 4:12]?

Al-Qurtubi (may Allaah
have mercy on him) said: “What is the reason why the legacy is mentioned
before the debt, when the debt takes precedence according to scholarly
consensus, i.e., the debts of the deceased must be paid off from his estate
before his will is executed… this may be answered in five ways: 

1 – What is meant is that
these two issues take precedence over the issue of inheritance, and the
order in which they are mentioned is not indicative of which one is more
important. Hence the bequest was mentioned first. 

2 – Because the legacy is
less binding than debt, it is mentioned first to show that it is
nevertheless important, as when Allaah says (interpretation of the
meaning): 

“What
sort of Book is this that leaves neither a small thing nor a big thing…”

[al-Kahf 18:49]

… 

4 – The legacy is mentioned first because it is the share of
the poor and needy, and the debt is mentioned second because it is the share
of the lender who can seek it with force and who has a strong argument to
support his case. 

5 – Because the legacy is something that is initiated by the
person, it is mentioned first, whereas the debt is something that is well
established and clear whether he mentioned it or not. 

See al-Jaami’ li Ahkaam al-Qur’aan by al-Qurtubi, vol.
5, p. 74. 

Some scholars added two extra points: 

“The legacy is mentioned first because the legacy is an act
of kindness and upholding family ties, unlike the debt which usually results
from a kind of neglect. So the phrase starts with the legacy because it is
of greater virtue.

And it was said that the legacy is mentioned first because it
is something that is given for nothing in return, whereas the debt is given
in return for something. So payment of the legacy is harder for the heirs
than payment of the debt, and paying the legacy may be thought of as a form
of waste, unlike the debt which the heir will pay with condifence.” 

See al-Tahqeeqaat al-Mardiyaah fi’l-Mabaahith al-Fardiyyah
by Shaykh Saalih al-Fawzaan, p. 27.