Selling goods on a commission basis
Q: Mrs J used to sell goods on behalf of Mr A, on a commission basis. After months of this trading, Mr A's sons began selling other goods to Mrs J's customers, Mr A then made a statement that his 2 sons will give Mrs J R1k each a month because of her these goods where being sold. For over a year this was being done, where Mrs J received R2k a month, and commission on the goods that she was to sell. In April of this year (2011), Mrs J asked for her commission of R8k which was due to her, Mr A then stated that over these past months the R2k a month was for her commission on the arranged goods as he did not make any arrangements for the R1k a month from each son. Mr A's son even said he was not aware that this had changed until his dad told him not to give the commission. What is the Shariah ruling according to this? Is Mr A liable to still pay Mrs J her commission that is due to her, and then request the change in her part of this agreement?