Salaah

Joining salaahs when travelling

Q: Is it permissible to join the salaahs when a person undertakes a journey and is a musafir? 

Example, you are leaving a country and it is zuhr time so before the flight you join Zuhr and asr? Or you visited a country and you go to a shop and maghrib time sets in so you read maghrib and Isha together? Is this permissible and if not, does one get a sin when they do it?

Performing salaah with impurity on one's body, clothing or salaah area

Q: Is someone who prays 5 times a day consistently with proper wudhu but knowingly and intentionally prays with impurity on the body, clothes or prayer area rejecting the obligation of purification, would this person be considered a disbeliever and be in hell forever? 

Is this person performing wudhu for each salah clearly showing that he is NOT rejecting the obligation of purification?

Imaam starting the qiraat while one is reciting thana

Q: In Prayer behind the Imam, if the Imam starts reciting whilst one just started reading the Thana and he was in the middle of saying اللهم in the Thana but the Imam had already started so he just finished saying Allahumma then he stopped reading the Thana, 

1. Would the prayer be valid? 

2. Would he have missed a Wajib and have to repeat the salah for missing a Wajib?

Following an imaam who makes masah over cotton socks

Q: I have a situation where in my work place in Saudi Arabia (far from any musjid in construction site), the person that often is imaam of the small musallah we perform zohr and asr salah, makes masah over his normal cotton socks when he makes wudu. 

I read salah for few months behind him and only found out about this recently. 

He confirmed that some scholars in Saudi passed a fatwa that its permissible. It would seem that many of the general public here follow this fatwa. 

I do not want to argue and create fitnah based on the situation. I know the fatwa is that wudu is not valid if masah is made over normal cotton socks based on majority opinion. 

However, based on my situation/ the fact that I did not know or could not control the imaam, is my previous salah valid or should I repeat it? 

Also, going forward, what should I do: Can I read salah behind him, based on the fact that I cannot control the imaam - perhaps consider him a different madhhab/ different opinion with salah being valid Insha Allah or is salah invalid for sure in which case. Should I read salah behind him and repeat it or should I try to avoid and read on my own. This will result in me not being able to make salah in jamaat at work and possibly create division. (Also reading salah and repeating is a challenge especially asr based on limited time and people observing you).