Non-traveller praying behind a imam who is a traveller

The Sunnah indicates that it is permissible for a non-traveller to pray behind a traveller, so long as the non-traveller offers his prayer in full and does not shorten it when the traveller imam does so. This was narrated in a hadeeth which is attributed to the Prophet (peace and blessings of Allaah be upon him) and in which there is some weakness, but it is in accordance with what is understood by the four madhhabs and others. 

It was narrated that ‘Imraan ibn Husayn (may Allaah be pleased with him) said: 

I went out on campaign with the Messenger of Allaah (peace and blessings of Allaah be upon him) and I was present with him at the conquest [of Makkah]. He stayed in Makkah for eighteen days, praying only two rak’ahs [in each four-rak’ah prayer], and he said: ‘O people of the city, pray with four rak’ahs, for we are people who are travelling.’” 

Narrated by Abu Dawood (no. 1229); classed as da’eef (weak) by al-Albaani in Da’eef Abi Dawood. 

Maalik narrated in al-Muwatta’ (2/206) from Ibn Shihaab from Saalim  ibn ‘Abd-Allaah from his father from ‘Umar ibn al-Khattaab that when he came to Makkah, he would lead them in praying two rak’ahs, then he would say: “O people of Makkah, complete your prayer for we are people who are travelling.” 

Ibn Qudaamah (may Allaah have mercy on him) said:  

The scholars are unanimously agreed that if the non-resident prays behind a traveller, and the traveller says the salaam after two rak’ahs, the non-traveller must offer the prayer in full. It was narrated that ‘Imraan ibn Husayn said:  I was present with the Messenger of Allaah (peace and blessings of Allaah be upon him) at the conquest [of Makkah]. He stayed in Makkah for eighteen days, praying only two rak’ahs [in each four-rak’ah prayer], and he said: ‘O people of the city, pray with four rak’ahs, for we are people who are travelling.’” Narrated by Abu Dawood. 

And because the prayer was obligatory for him with four rak’ahs, so he does not have the right to omit any of its rak’ahs, as would also have been the case if he had not been led in prayer by a traveller. End quote. 

Al-Mughni (2/64). 

Al-Kaasaani al-Hanafi (may Allaah have mercy on him) said: 

A non-traveller following a traveller (in prayer) is valid … then when the imam says the salaam after praying two rak’ahs, the non-traveller should not say the salaam, because he still has to complete his prayer, and if he were to say the salaam (at this point) his prayer would be invalidated. Rather he should stand up and complete the prayer with four rak’ahs, because the Prophet (peace and blessings of Allaah be upon him) said: “Complete it, O people of Makkah, for we are people who are travelling.” 

When the imam who is travelling says the salaam, he should say to the non-travellers who are behind him: “Complete your prayer, for we are people who are travelling,” following the example of the Prophet (peace and blessings of Allaah be upon him). End quote. 

Badaa’i’ al-Sanaa’i’ (1/101). 

Shaykh Ibn Baaz (may Allaah have mercy on him) said: 

If a non-traveller offers an obligatory prayer such as Zuhr or ‘Asr or ‘Isha’ behind a traveller, then he must pray four rak’ahs. Hence he must complete his prayer after the traveller says the salaam following two rak’ahs. End quote. 

Majmoo’ Fataawa Ibn Baaz (12/259). 

Shaykh Ibn ‘Uthaymeen (may Allaah have mercy on him) said: 

It is permissible for the traveller to be an imam for non-travellers, and when he says the salaam, the non-travellers should stand up and complete the prayer after he has finished. But the traveller who leads non-travellers in prayer should tell them before he prays, “We are travelling so when we say the salaam, complete the prayer,” because the Prophet (peace and blessings of Allaah be upon him) prayed in Makkah after the conquest and said: “Complete [your prayers] O people of Makkah, for we are people who are travelling.” And he would lead them in praying two rak’ahs, and they would complete their prayers after he had finished. End quote. 

Majmoo’ Fataawa wa Rasaa’il al-Shaykh Ibn ‘Uthaymeen (15/153) 

See also Nayl al-Awtaar (3/199), al-Mawsoo’ah al-Fiqhiyyah (6/33). 

And Allaah knows best.