98. The major cause of the setback suffered at Uhud was that precisely at the moment of their victory the Muslims succumbed to the desire for worldly possessions, and turned to collecting booty rather than completing their task of crushing the enemy. Hence God thought fit to raise a barrier against this excessive adoration of money, and to urge them to give up usury which keeps man constantly absorbed in considering ways and means of amassing wealth and generally whets his appetite for money.
99. The existence of interest in a society generates two kinds of moral disease. It breeds greed and avarice, meanness and selfishness among those who receive interest. At the same time, those who have to pay interest develop strong feelings of hatred, resentment, spite and jealousy. God intimates to the believers that the attributes bred by the spread of interest are the exact opposite of those which develop as a result of spending in the way of God, and that it is through the latter rather than the former that man can achieve God's forgiveness and Paradise. (For further explanation see (Surah 2, n. 320 above.)
100. This alludes to the Battle of Badr. The intention is to point out to the Muslims that if the unbelievers were not demoralized by the setback they suffered at Badr then the Muslims should not be disheartened by the setback thev suffered in the Battle of Uhud.
101. The actual words of this verse, can be interpreted in two ways. One meaning could be that God wanted to select some of them so that He could bestow upon them the honour of martyrdom. The second meaning could be that out of the hotch-potch of true believers and hypocrites which their community consisted of at that moment, God wanted to sift those who were truly His witnesses over all mankind. See( Qur'an 2: 143 - Ed.)