After Allah mentioned the rulings for fasting and Jihad, he explained the rituals by commanding the Muslims to complete Hajj and `Umrah, meaning, to finish the rituals of Hajj and `Umrah after one starts them. This is why Allah said afterwards:

﴿فَإِنْ أُحْصِرْتُمْ﴾

(But if you are prevented) meaning, if your way to the House is obstructed, and you are prevented from finishing it. This is why the scholars agree that starting the acts of Hajj and `Umrah requires one to finish them. As for Makhul, he said, "Complete, means to start them from the Miqat (areas the Prophet designated to assume Ihram from).'' `Abdur-Razzaq said that Az-Zuhri said: "We were told that `Umar commented on:

﴿وَأَتِمُّواْ الْحَجَّ وَالْعُمْرَةَ لِلَّهِ﴾

(And complete Hajj and `Umrah for Allah.) "Complete Hajj and `Umrah means performing each of them separately, and to perform `Umrah outside of the months of Hajj, for Allah the Exalted says:

﴿الْحَجُّ أَشْهُرٌ مَّعْلُومَـتٌ﴾

(The Hajj (pilgrimage) is (in) the well-known (lunar year) months. )''

As-Suddi said,

﴿وَأَتِمُّواْ الْحَجَّ وَالْعُمْرَةَ لِلَّهِ﴾

(And complete Hajj and `Umrah for Allah.) means, "Maintain the performance of Hajj and `Umrah.'' Ibn `Abbas was reported to have said, "Hajj is `Arafat, while `Umrah is Tawaf.'' Al-A`mash related that Ibrahim said that `Alqamah commented on Allah's statement:

﴿وَأَتِمُّواْ الْحَجَّ وَالْعُمْرَةَ لِلَّهِ﴾

(And complete Hajj and `Umrah for Allah.) "Abdullah (Ibn Mas`ud) recited it this way: `Complete Hajj and `Umrah to the House, so that one does not exceed the area of the House during the `Umrah'.'' Ibrahim then said, "I mentioned this statement to Sa`id bin Jubayr and he said; `Ibn `Abbas also said that.''' Sufyan reported that Ibrahim said that `Alqamah said (regarding the Ayah 2:196), "Perform the Hajj and `Umrah to the House.'' Ath-Thawri reported that Ibrahim read (the Ayah), "Perform the Hajj and `Umrah to the House.''