"Can a ... leopard change his spots? Neither can you do good who are accustomed to doing evil.
" - Jeremiah 13:23
There are a number of professing Christians who have actually been taught that God would never require us to do anything we are incapable of doing. But does not the whole Bible teach that we are required to obey the Law? Yet not one person, save Jesus, can perfectly obey the law? In fact, Paul declares that the purpose of the Divine legislation was not to show our moral ability, but to reveal sin i.e.. our utter inability and impotence to obey the law (see Rom 3:19, 20). Further, there was nothing that obligated God to send His Son to redeem us. He could have justly required the fallen human race to obey the Law and left us to ourselves to try ... and then He could have swept us all away in judgment when each of us failed to do so.
That people are accountable to do things they are incapable of doing is also evident in every day life. Consider those who borrow large sums of money from the bank and then lose it all through some foolish act. Their inability to repay the bank in no way alleviates them from the responsibility to do so. If the Arminian makes the charge that inability alleviates responsibility, then it follows that once I squandered the money away then I am no longer responsible to repay it. That I am off the hook. But we all know this is not the case. Likewise, in Adam, we all owe a sin-debt that we cannot repay. The Arminian reasons that we are therefore no longer responsible for it if we can do nothing about it.