Praise be to Allah.
Ruling on buying and selling after the call to Jumu‘ah prayer
It is prohibited to engage in trade by buying and selling after the call to Jumu‘ah prayer . Allah, may He be exalted, says (interpretation of the meaning):
“O you who have believed, when [the adhan] is called for the prayer on the day of Jumu‘ah [Friday], then proceed to the remembrance of Allah and leave trade. That is better for you, if you only knew” [al-Jumu‘ah 62:9].
Ibn Katheer (may Allah have mercy on him) said:
“leave trade” means: hasten to remember Allah and stop trading when you are called to prayer. Hence the scholars are unanimously agreed that it is haraam to buy and sell after the second call [for Jumu‘ah prayer].
End quote from Tafseer Ibn Katheer (8/122).
The reason for the prohibition on buying and selling after the call to Jumu‘ah prayer
The reason for the prohibition on buying and selling at the time of Jumu‘ah is that trading at the time of Jumu‘ah will distract the one who does that from listening to the khutbah and from the prayer, which are what is referred to by the phrase “the remembrance of Allah” in the verse quoted above. Based on that, the prohibition includes every interaction that will distract a person from Jumu‘ah; the prohibition does not apply only to ordinary buying and selling.
Ibn al-‘Arabi (may Allah have mercy on him) said:
The words of Allah, may He be exalted, “leave trade”: there is scholarly consensus that this is to be followed, and there is no difference of scholarly opinion concerning the prohibition on buying and selling… because buying and selling are only prohibited so that one will not be distracted by that. Anything that will distract one from Jumu‘ah, such as trading, all of it is prohibited according to Islamic teachings. End quote from Ahkaam al-Qur’an (1805-1806).
Shaykh ‘Abd ar-Rahmaan as-Sa ‘di (may Allah have mercy on him) said:
The sixth and seventh principles: if the contract involves omitting something that is obligatory, or doing something that is forbidden, then it is haraam and is not valid. The religious texts confirm these two issues in several places, including the following:
Buying and selling after the call to Jumu‘ah prayer, or if one is running out of time to offer an obligatory prayer, or if there is the fear of missing prayer in congregation. The same applies to any interaction that could cause a person to miss out on, or distract him from, duties that Allah has made obligatory for him. Allah, may He be exalted, says (interpretation of the meaning):
“O you who have believed, let not your wealth and your children divert you from remembrance of Allah. And whoever does that - then those are the losers” [al-Munaafiqoon 63:9].
This applies if one is distracted from doing obligatory duties, because the verse forbids that, then speaks of the loss that results from it. End quote from Irshaad Ooli’l-Basaa’ir (p. 192).
Ruling on digital trade at the time of Jumu‘ah
Once this is established, being distracted by digital trade at the time of Jumu‘ah is haraam, just like being distracted by ordinary trade , and there is no difference. Seeing that the times of prayer vary from one city to another, it is a good idea to put a note on your website stating that purchasers – if they are among those for whom Jumu‘ah prayer is obligatory – should pay attention to the sanctity of the time for Jumu‘ah prayer and not make any purchases at that time.
And Allah knows best.