ANSWER:

Praying while standing when able is one of the pillars without which prayer is invalid. 

However if you’re not able to stand and pray, then you can sit on a chair and pray because Allah does not burden a soul beyond his or her capacity.
You should not keep any table in front of you. You can simply bend a little for ruk’u while sitting in the chair and bend a little further for sujood while keeping your hands on your knees or your thighs. 

Salam my bro I would like to know can one sit on a chair and pray because of health issues like I have a problem with my hip and knee I can not sit on the floor at all and have been told by an imam my prayers are not valid because I can’t go down to do sajude plz bro can u tell me if this is the case also he said u have to have a table in front of u bro plz advice me what’s authentic

Prayer | April 7, 2018 9:06 am
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Some old men raise their pants above stomach, as a result the pant seems to be hugging private part while doing sujood. If they consider that lowering the pant is todays fashion and don’t want to do it, how can we advice thm in this regard?
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Is it permissible to make dua in the end of our fard salah when offered in congregation(jamaat) this only delays saying of salam to both sides by 1-2 minutes after imam said salam(to conclude prayer)