Can I fast six (days) of Shawwal before making up for the missed days of Ramadān?
*Response:*
This matter deals with ruling on performing a voluntary act before making up for the missed obligatory act.
The basic principle is that voluntary fast is not permitted before making up missed days of Ramadān.
This is based on the jurisprudential principle that says: *"No act can make an obligatory act abandoned (put aside) except an obligatory act."*
Be as it may be, *there are three (3) different opinions of the scholars on the matter and this of course, has shown the beauty, uniqueness and simplicity of Islām:*
1⃣ *It is NOT allowed to fast six (6) days of Shawwal before repayment of the missed days of Ramadān.* This is based on the jurisprudential principle earlier quoted (above). As an addendum, Abū Hurairah (may Allāh be pleased with him) said that *he who observes voluntary fast and has some days to make up for in Ramadān but does not do so, his fasts won't be accepted until he does so.* See Ahmad in his Masnad 2/352, At-Tabarāni in Al-Awsat. Said Al-Haithami in Majma' Zawā'id 3/179 that the hadīth is hasan.
2⃣ *One is allowed to benefit from the virtues of the 6 (days fast) of Shawwal for its period is short as compared to the period of making up for missed days of Ramadān that is lengthy*. Says Allāh: *"but whoever among you is sick or on a journey, then (he shall fast) a (like) number of other days"* So there is no specific time stated here for the "make up". In addition, the six (6) days fast measured and likened to observance of Nāfilah during the timing of obligatory Salāh. Imām Ahmad Hanbali reiterated this in his explanation of "Al-Ashbāh wan nadhā'ir filqawā'id wal furu'.
3⃣ *The two fast could be combined and observed at the same time. This is simply achieved by combining two intentions together.* As such, one is allowed to make up missed days of Ramadān in the first ten days of Dhul Hijjah thereby earning the rewards of those days too or fasting six days of Shawwal with the intention of making up for the missed days of Ramadān thereby earning two rewards simultaneously.
The proof on this opinion are: (1) It has been reported that 'Umar bn Al-Khattab loves making up his missed days of Ramadān in Dhul Hijjah. (2) Similar acts of worship are allowed to be done with combined intentions. For instance, combining intention of Friday Ghusl with Ghusl Janabah, combining intentions of Tahiyyatul Masjid with the compulsory Salāh as said by Imām Mālik. And there could be an instance of making up Salāh during the period of Duha or Qiyāmul Lail earning the rewards of those periods too.
Therefore, it's allowed to fast during those special days, Shawwal inclusive, to *save time and have rewards for the two acts easily which could have been done separately*
*Which of these is most preferred?:*
No opinion is most superior or preferred for we have been allowed to pick anyone that will pleases us. If one chooses to pay up for the missed days of Ramadān and observe the 6 (days) of Shawwal, that is best. But if this will pose challenge & be difficult, let him fast Shawwal first and delay making up for Ramadān. That is also best. And if he combines intenhtions thereby observing Shawwal and at the same time making up for Ramadān, that is also best.
*Allāh knows best*
Yes you can do it. This sacrifice is beneficial.