Praise be to Allah.
The scholars (may Allah have mercy on them) differed concerning the length of stay during which a traveller might shorten his prayers and if he stays longer than that he must offer the prayers in full. There are many different opinions. The four madhhabs say that if the traveller’s stay does not exceed three days, then he may avail himself of the concession granted to travellers.
Ibn Rushd said:
With regard to the differences of opinion concerning the period of stay in a place during which it is permissible for a traveller to shorten his prayers, there is a great deal of difference. Abu ‘Umar – meaning Ibn ‘Abd al-Barr – narrated approximately eleven different views, but the most well known views are those of the well known fuqaha’, among whom there are three opinions:
1-The view of Maalik and al-Shaafa’i, which is that if the traveller decides to stay for four days, he should offer the prayers in full.
2-The view of Abu Haneefah and Sufyaan al-Thawri, which is that if he decides to stay for fifteen days, he should offer the prayers in full.
3-The view of Ahmad and Dawood, which is that if he decides to stay for more than four days he should offer the prayers in full.
The reason for this difference of opinion is that it is a matter concerning which sharee’ah is silent and using analogy is regarded as a weak method by all. Hence all of these scholars tried to quote as evidence for their views different scenarios which were narrated from the Prophet (peace and blessings of Allah be upon him), in which he stayed in a place and shortened his prayers or he applied the ruling of travel to a situation.
Bidaayat al-Mujtahid, 1/122, 123
Based on this, the case asked about here, which is that of a traveller who stays in a place for one day, does not fall into the area concerning which there is this difference of opinion among the imams, so he should shorten his prayers.
With regard to joining the prayers: if he is on the road, then it is better for him to join Zuhr and ‘Asr, and Maghrib and ‘Isha’, at the time of the earlier or later prayer according to what is easiest for him.
When he has stopped in a place (such as when he has reached the city to which he is travelling, or he has stopped en route for a few hours to rest) then it is better for him not to join them, but if he does join them then there is no sin on him, because both options were narrated in saheeh reports from the Messenger of Allah (peace and blessings of Allah be upon him).
The apparent meaning of the words “on a journey during which it is permissible to shorten one’s prayers” is that it is permissible for a traveller to join his prayers whether he has stopped or is on the road. There is a difference of opinion among the scholars concerning this matter.
Some of them said that it is not permissible for the traveller to join his prayers except whilst he is on the road, not when he has stopped.
They quoted as evidence the hadeeth of Ibn ‘Umar: The Prophet (peace and blessings of Allah be upon him) used to join Maghrib and ‘Isha’ when he was travelling (when he was on the road).
And they quote the fact that the Prophet (peace and blessings of Allah be upon him) did not join two prayers in Mina during the Farewell Pilgrimage, because he had made stop, but he was undoubtedly still a traveller because he shortened the prayers.
The second view is that it is permissible for the traveller to join the prayers whether he has made a stop or is on the road.
They quoted the following as evidence:
1 – The fact that the Prophet (peace and blessings of Allah be upon him) joined the prayers during the campaign of Tabook when he had made a stop.
2 – The apparent meaning of the hadeeth of Abu Juhayfah which is proven in al-Saheehayn: that the Prophet (peace and blessings of Allah be upon him) made a stop in al-Abtah during the Farewell Pilgrimage, and he came out one day wearing a red hullah (suit) and led the people in praying Zuhr with two rak’ahs and ‘Asr with two rak’ahs. They said that the apparent meaning of this hadeeth is that these two prayers were joined.
3 – The general meaning of the hadeeth of Ibn ‘Abbaas which says that the Messenger (peace and blessings of Allah be upon him) joined Zuhr and ‘Asr, and Maghrib and ‘Isha’, in Madeenah when there was no fear and no rain.
4 – That if it is permissible to join prayers in the case of rain etc, then it is more appropriate that it be permissible in the case of travel.
5 – That it is difficult for a traveller to offer each prayer at its proper time, either because of inconvenience or because there is no water available, or for some other reason.
The correct view is that it is permissible for the traveller to join his prayers, but it is mustahabb in the case of one who is on the road and is permissible but not mustahabb for one who has made a stop: if he joins his prayers there is nothing wrong with that but if he does not join them, that is better.
Al-Sharh al-Mumti’, 4/387-390
See also the answer to question no. 50312
And Allah knows best.