Ka'b swore to him: "By Allah (SWT) Who parted the sea for Musa, we find in the Tawrah that when Dawud, the Prophet of Allah, finished his prayer, he would say: 'Allahumma Aslih li dinya-lladhi ja'altahu li ismatan wa aslih li dunyaya-llati ja'alta fiha ma'ashi, Allahumma inni a-udhu biridaka min sakhatik wa a-udhu bi'afwika min naqmatika wa a-udhu bika mink, la mani' lima a'taita wa la mu'tia lima mana'ta wa la yanfa'u dhal-jaddi minka al-jadd (O Allah, set straight my religious commitment that You have made a protection for me, and set straight my worldly affairs which You have made a means of my livelihood. O Allah, I seek refuge in Your pleasure from Your wrath, and I seek refuge in Your forgiveness from Your punishment, and I seek refuge in You from You. None can withhold what you have given and none can give what you have withheld, and no wealth or fortune can avail the man of wealth and fortune before You.)'" He said: "And Ka'b told me that Suhaib told him that Muhammad (ﷺ) used to say (these words) when he had finished praying.'"
Sunan an-Nasa'i Book 13, Hadith 168
While we were sitting with the Prophet (ﷺ) a man came and said, "O Allah's Messenger (ﷺ)! I have been ruined."
Allah's Messenger (ﷺ) asked what was the matter with him. He replied "I had sexual intercourse with my
wife while I was fasting." Allah's Messenger (ﷺ) asked him, "Can you afford to manumit a slave?" He replied
in the negative. Allah's Messenger (ﷺ) asked him, "Can you fast for two successive months?" He replied in
the negative. The Prophet (ﷺ) asked him, "Can you afford to feed sixty poor persons?" He replied in the
negative. The Prophet (ﷺ) kept silent and while we were in that state, a big basket full of dates was
brought to the Prophet (ﷺ) . He asked, "Where is the questioner?" He replied, "I (am here)." The Prophet (ﷺ)
said (to him), "Take this (basket of dates) and give it in charity." The man said, "Should I give it to a
person poorer than I? By Allah; there is no family between its (i.e. Medina's) two mountains who are
poorer than I." The Prophet (ﷺ) smiled till his premolar teeth became visible and then said, 'Feed your
family with it."
Sahih al-Bukhari Book 30, Hadith 43
Yahya related to me from Malik from a reliable source from Amr
ibn Shuayb from his father from his father's father that the Messenger
of Allah, may Allah bless him and grant him peace, forbade
transactions in which nonrefundable deposits were paid.
Malik
said, "That is, in our opinion, but Allah knows best, that for
instance, a man buys a slave or slave-girl or rents an animal and then
says to the person from whom he bought the slave or leased the animal,
'I will give you a dinar or a dirham or whatever on the condition that
if I actually take the goods or ride what I have rented from you, then
what I have given you already goes towards payment of the goods or
hire of the animal. If I do not purchase the goods or hire the animal,
then what I have given you is yours without liability on your part.' "
Malik said, "According to the way of doing things with us
there is nothing wrong in bartering an arabic speaking merchant slave
for abyssinian slaves or any other type that are not his equal in
eloquence, trading, shrewdness, and know-how. There is nothing wrong
in bartering one slave like this for two or more other slaves with a
stated delay in the terms if he is clearly different. If there is no
appreciable difference between the slaves, two should not be bartered
for one with a stated delay in the terms even if their racial type is
different."
Malik said, "There is nothing wrong in selling
what has been bought in such a transaction before taking possession of
all of it as long as you receive the price for it from some one other
than the original owner."
Malik said, "An addition to the
price must not be made for a foetus in the womb of its mother when she
is sold because that is gharar (an uncertain transaction). It is not
known whether the child will be male or female, good-looking or ugly,
normal or handicapped, alive or dead. All these things will affect the
price."
Malik said that in a transaction where a slave or
slave-girl was bought for one hundred dinars with a stated credit
period that if the seller regretted the sale there was nothing wrong
in him asking the buyer to revoke it for ten dinars which he would pay
him immediately or after a period and he would forgo his right to the
hundred dinars which he was owed.
Malik said, "However, if
the buyer regrets and asks the seller to revoke the sale of a slave or
slave-girl in consideration of which he will pay an extra ten dinars
immediately or on credit terms, extended beyond the original term,
that should not be done. It is disapproved of because it is as if, for
instance, the seller is buying the one hundred dinars which is not yet
due on a year's credit term before the year expires for a slave-girl
and ten dinars to be paid immediately or on credit term longer than
the year. This falls into the category of selling gold for gold when
delayed terms enter into it."
Malik said that it was not
proper for a man to sell a slave-girl to another man for one hundred
dinars on credit and then to buy her back for more than the original
price or on a credit term longer than the original term for which he
sold her. To understand why that was disapproved of in that case, the
example of a man who sold a slave-girl on credit and then bought her
back on a credit term longer than the original term was looked at. He
might have sold her for thirty dinars with a month to pay and then buy
her back for sixty dinars with a year or half a year to pay. The
outcome would only be that his goods would have returned to him just
like they were and the other party would have given him thirty dinars
on a month's credit against sixty dinars on a year or half a year's
credit. That was not to be done.
Muwatta Malik Book 31, Hadith 1