sins are of three kinds...

sins are of three kinds, each has its own way of repentance: what belongs to people: such as stealing from other's property, whether small or large. its repentance is to return that to the person, if the owner is known or give it to the poor if the owner is unknown. what belongs to god: such as prayers and fasting. if they were missed, the repentance is to make up that prayer and fasting.

in the case of fasting, it may apply some kaffara i.e., if one missed intentionally, he has to fast sixty days for each missed day or to feed 60 persons for each missed day of fasting. for forbidden actions and the grave sins: it differs from one to another such as to lie, drinking, etc. in general the repentance is to decide firmly not to go back to these actions.

certainly almighty god has laid down the rules as he says in the holy qur'an, "he accepts repentance from his servants and forgives their faults". the qur'an 42:25 can one join two prayers? it is highly recommended to pray exactly on time. however, it is permitted to join two prayers at one time. for example, to perform the asr prayer immediately after the noon . or to delay the noon prayer to the later time before sunset. this also applies to the sunset and evening prayers.

the validity of such an opinion is based on many hadiths. among them is what is reported by al-bukhari that ibn abbas said ; "indeed the prophet did pray in madina seven and eight . the ( prayers of) noon, afternoon, sunset, and evening ." see bukhari, v 1, page 136, cairo. muslim, in his work, reports that ibn abbas said that the messenger of allah joined (prayers) in madina without having any fear or being on a journey.

when ibn abbas was asked about the reason, he said; "[the prophet] did not want to make it difficult for his nation ." see muslim, v. 2, page 151. cairo. should we prostrate on earth? it is an obligatory to prostrate (do sajdah) on a pure surface of the ground or on whatever grows from the earth which is used neither for food nor for clothing . the prophet says ; "the earth has been created to be used as place for prostration and as detergent, "i.e., for both sajdah and tayammum.

see al-bukhari, v. 1 page 112, cairo. nowadays, since the grounds of most of the mosques and residences are covered by carpets, it is necessary to have some pure soils or a pure rock to use it for sajdah.