InshaAllah I will discuss about fasting of six days of Shawwal in very brief tweets so that it clarifies the questions which are raised at this time, and it is on the issue of preference of six fasts of Shawwal over the pending fasts of Ramadan.
The evidence of six fasts of Shawwal is the saying of Noble Prophet Peace Be Upon Him: "The one who fasts Ramadan and then follows it with Six in Shawwal is like fasting the whole year" : Narrated by Muslim and others.
It is taken from the narration of the Noble Prophet Peace Be Upon Him "The one who fasts Ramadan" meaning the whole of Ramadan because fasting of full Ramadan in obligatory. Even if someone were to say that this narration fulfils to those whose fast the majority of Ramadan, we would say such interpretation is not evidenced in the text of narration.
The Noble Prophet Peace Be Upon Him has decreed a reward of full year of fasting for the one who fasts the full Ramadan and follows it with six in Shawwal because it comes in another narration that good deeds are rewarded by ten times. So Ramadan rewards for ten months and six in Shawwal rewards for two months.
The word "then" describes a sequence as is defined with the language experts and if the six fasts are preferred over the overdue fasts, it would clearly breach this definition and purpose and would be difficult to answer on.
The one who promotes the fasting of six in Shawwal above the overdue fasts has reversed the text of narration
and would mean that he has fasted six in Shawwal and then followed it with some from Ramadan. This is the core part of the narration.
The narration appears to validate the reward of fasting of whole year until the end of Shawwal. And this could, in some cases, not be achieved with those who promote the six over the pending fasts as it might prolong them beyond Shawwal end.
The basis of religious interpreting texts is to take from its appearance unless otherwise there is an evidence from Quran and Sunnah to revoke it. And anything apart from it has a visible burden.
The majority of beginning and previous interpreting scholars have not said of promoting the six fasts over the pending fasts of Ramadan in practical application of the narration "Fulfill the pending towards Allah for Allah is righteous of being fulfilled"
The evidence of those who promote by saying that Aisha, May Allah be pleased with her, used to delay the pending fasts does not consider that such negligence in six fasts of Shawwal is not an evidence which can be based upon because of two reasons.
Firstly, It is not mentioned in the narration that Aisha, May Allah be pleased with her, fasted the six fasts of Shawwal. So we cannot ignore the narration appearance just because of our assumption for which we have no evidence because we do not know when were the six fasts of Shawwal decreed.
Secondly, Aisha, May Allah be pleased with her, used to delay the pending fasts due to rank of Prophet Peace Be Upon Him and his requirements. This reason is also valid in the six fasts even if it were nifl but the combined meaning is the same.
Those who promote the six fasts of Shawwal over the pending fasts of Ramadan need to answer two questions which are the cause of objection and which are difficult to answer without assumptions and unguided rulings.
First Question: If a person did not fast in Ramadan except a day only then it will obligate him to fast the six days of Shawwal and thereafter fast the 29 pending fasts which is quite far.
Second: But if he did not fast the whole Ramadan for some reason, he will be obliged to fast the six days of Shawwal before fasting any single fast of Ramadan and this is in complete contradiction of the narration text.
And therefore there is nothing superior and safer than to stop at the text of the narration and not overburden in bearing what cannot be borne due to assumptions and possibilities without any valid evident narration.
And at the end of the topic, The saying that the one who abstained from fasting due to some reason is like the one who fasted Ramadan has no place in this reasoning because the Noble Messenger Peace Be Upon Him attached the decree in his narration by fasting of Ramadan and not by witnessing the month.