There is no restriction on the blind, nor any restriction on the lame, nor any restriction on the sick, nor on yourselves, if you eat from your houses, or the houses of your fathers, or the houses of your mothers, or the houses of your brothers, or the houses of your sisters, or the houses of your father"s brothers, or the houses of your father"s sisters, or the houses of your mother"s brothers, or the houses of your mother"s sisters, or (from that) whereof you hold keys, or (from the house) of a friend. No sin on you whether you eat together or apart. But when you enter the houses, greet one another with a greeting from Allah (i.e. say: As-Salamu"Alaikum - peace be on you) blessed and good. Thus Allah makes clear the Ayat (these Verses or your religious symbols and signs, etc.) to you that you may understand.
The true believers are only those, who believe in (the Oneness of) Allah and His Messenger (Muhammad SAW), and when they are with him on some common matter, they go not away until they have asked his permission. Verily! Those who ask your permission, those are they who (really) believe in Allah and His Messenger. So if they ask your permission for some affairs of theirs, give permission to whom you will of them, and ask Allah for their forgiveness. Truly, Allah is Oft-Forgiving, Most Merciful.
Make not the calling of the Messenger (Muhammad SAW) among you as your calling of one another. Allah knows those of you who slip away under shelter (of some excuse without taking the permission to leave, from the Messenger SAW). And let those who oppose the Messenger"s (Muhammad SAW) commandment (i.e. his Sunnah legal ways, orders, acts of worship, statements, etc.) (among the sects) beware, lest some Fitnah (disbelief, trials, afflictions, earthquakes, killing, overpowered by a tyrant, etc.) befall them or a painful torment be inflicted on them.
Certainly, to Allah belongs all that is in the heavens and the earth. Surely, He knows your condition and (He knows) the Day when they will be brought back to Him, then He will inform them of what they did. And Allah is All-Knower of everything.