1. Do not force yourself into the front saff if there is insufficient space, thereby causing inconvenience to others.
عن عبد الله بن بسر رضي الله عنه قال جاء رجل يتخطى رقاب الناس يوم الجمعة والنبي صلى الله عليه وسلم يخطب فقال له النبي صلى الله عليه وسلم اجلس فقد آذيت (سنن أبي داود، الرقم: 1120)
Hazrat Abdullah bin Busr (radhiyallahu anhu) reports that on one occasion, a person entered the musjid on the Day of Jumuah while Hazrat Rasulullah (sallallahu alaihi wasallam) was delivering the khutbah. The man began climbing over the shoulders of people (trying to reach the front saff). Hazrat Rasulullah (sallallahu alaihi wasallam) (reproached him) saying, “Sit down, for certainly you have caused inconvenience (to the people).”
عن سهل بن معاذ بن أنس الجهني عن أبيه رضي الله عنه قال قال رسول الله صلى الله عليه وسلم من تخطى رقاب الناس يوم الجمعة اتخذ جسرا إلى جهنم (سنن الترمذي، الرقم: 513)
Hazrat Mu’aaz bin Anas (radhiyallahu anhu) reports that Hazrat Rasulullah (sallallahu alaihi wasallam) said, “The one who climbs over the shoulders of people on the Day of Jumuah has made a bridge for himself to Jahannum.”
2. You should not perform salaah in such a place in the musjid that obstructs the free movement of the musallisg. performing salaah at the entrance, thereby preventing others from passing.
عن ابن عمر رضي الله عنهما أن رسول الله صلى الله عليه وسلم نهي أن يصلى في سبعة مواطن … وقارعة الطريق … (سنن الترمذي، الرقم: 346)
Hazrat Ibnu Umar (radhiyallahu anhuma) reports that Hazrat Rasulullah (sallallahu alaihi wasallam) prohibited performing salaah in seven places; (and from them is) on the pathway.
3. If you are in a musjid-e-kabeer (334,451 m2 or larger), then it will be permissible for you to pass in front of those performing salaah, provided you avoid walking on their place of sajdah (i.e. there should be the amount of one saff or more between you and those performing salaah).
4. If you are in a musjid-e-sagheer (a musjid which is smaller than 334,451 m2) then it is not permissible for you to pass in front of those performing salaah. However, if a sutrah is placed in front of those performing salaah, then passing in front of them will be permissible.
عن أبي جهيم رضي الله عنه قال قال رسول الله صلى الله عليه وسلم لو يعلم المار بين يدي المصلي ماذا عليه لكان أن يقف أربعين خيرا له من أن يمر بين يديه قال أبو النضر لا أدري أقال أربعين يوما أو شهرا أو سنة (صحيح البخاري، الرقم: 510)
Hazrat Abu Juhaim (radhiyallahu anhu) reports that Hazrat Rasulullah (sallallahu alaihi wasallam) said, “If the one crossing in front of a musalli only knew the severity of his action, then waiting for forty would have been better for him than crossing in front of him (i.e. the person performing salaah).” Abu Nadhr says, “I do not know whether he intended forty days, forty months or forty years.” (In other Ahaadith, mention is made of forty years.)
5. It is not permissible to remove any item from the musjid that has been given as waqf for the musjid.