Is it obligatory for someone who has committed to prayer at the age of 20 to make up the missed prayers from previous years according to the Shafi'i school of thought?

According to the majority of scholars, missed prayers from the time of puberty until repentance must be made up. Imam An-Nawawi transmitted the scholarly consensus on this matter. Abu Muhammad Ali ibn Hazm dissented, stating that such prayers can never be made up, but rather one should increase in good deeds and supererogatory prayers. This view contradicts the consensus and is invalid in terms of evidence.

Evidence for the obligation of making up prayers includes the hadith of Abu Hurayrah (may Allah be pleased with him) that the Prophet (peace be upon him) commanded the one who engaged in sexual intercourse during the day in Ramadan to fast one day in addition to the expiation. Furthermore, if making up is obligatory for one who missed a prayer forgetfully, then it is even more so for one who missed it intentionally.

The Shafi'is hold that making up intentionally missed prayers is obligatory immediately, which is the soundest opinion within their school. As for the order of making up missed prayers, it is not obligatory according to them, but rather recommended. If one remembers a missed prayer when the time for the current prayer is short, one must begin with the current prayer.