The fifth condition is to say the khutba  before the salat. It must be said in the presence of discreet men who have reached the age of puberty. But it is not a condition for the jama'at  to understand it.
The sixth condition is to perform the Friday prayer in jama'at. It is acceptable if the entire jama'at listening to the khutba leave and other people come and perform the salat. The jama'at may also be formed by musafirs (visitors) or by the invalid in Hanafi Madhhab  .
The seventh condition is for the mosque to be open for everybody. If the door is locked and the salat is performed inside the mosque it will not be accepted. However, it does not hurt the salat not to allow women into the mosque in order to prevent fitna  .
 khutba: the preaching delievered at mosque; the homily delivered at the pulpit by the imam at Jum'a and 'Iyd prayers ( at the prayers of Friday and of Islamic festivals), which must be read in Arabic all over the world (sinful if read in another language).
 jama'at: a congregation of Muslims. One person performs namaz in the front; the others, behind him, preform it like him by adapting themselves to him. The person who performs it in the front is called the imam. Those who perform it behind him are called the jama'at.
 madhhab: all of what a profound 'alim of (especially) Fiqh (usually one of the four-Hanafi, Shafi'i, Maliki, Hanbali) or iman (one of the two, namely Ash-ari, Maturidi) communicated.
 fitna: the widespreading of statements and actions that harm Muslims and Islam. : disunion among Muslims.