How was william wilberforce, a member of parliament, able to affect the future of slavery in britain

In 1807, he achieved a ban on British slave trade.

William Wilberforce, a member of Parliament was able to affect the future of slavery in Britain, because he helped pass the Slave Trade Act of 1807 and later on the Slavery Abolition Act of 1833 which abolished slavery in all British colonies. This included slave trade and all other things related to slavery being abolished in the Indian subcontinent, African colonies and colonies in the Caribbean.