When Muhammad bin Qasim began the conquest of Sindh, he exercised the policy of converting the people of a territory, which gave a fight, at the pain of death. He gave quarters to the people, if they submitted to his invading army without giving a fight. He did not force them to convert. When the report of his latter lenient policy reached his patron Hajjaj in Baghdad, disapproving the leniency, he wrote to Qasim:
‘…I learnt that the ways and rules you follow are conformable to the (Islamic) Law. Except that you give protection to all, great and small alike, and make no difference between enemy and friend. God says, ‘Give no quarter to Infidels, but cut their throats.’ Then know that this is the command of the great god. You should not be too ready to grant protection… After this, give no protection to any enemy except to those who are of rank (i.e., accept Islam). This is a worthy resolve, and want of dignity will not be imputed to you.’

What It Means

This is a placeholder explanation generated by the low-overhead model. It interprets "When Muhammad bin Qasim began the conquest of Sindh, he exercised the policy of converting the people of a territory, which gave a fight, at the pain of death. He gave quarters to the people, if they submitted to his invading army without giving a fight. He did not force them to convert. When the report of his latter lenient policy reached his patron Hajjaj in Baghdad, disapproving the leniency, he wrote to Qasim:
‘…I learnt that the ways and rules you follow are conformable to the (Islamic) Law. Except that you give protection to all, great and small alike, and make no difference between enemy and friend. God says, ‘Give no quarter to Infidels, but cut their throats.’ Then know that this is the command of the great god. You should not be too ready to grant protection… After this, give no protection to any enemy except to those who are of rank (i.e., accept Islam). This is a worthy resolve, and want of dignity will not be imputed to you.’" in the context of "Elliot and Dowson, Vol I, 173ff. Letter to M. bin Qasim." to mean that wisdom is timeless.