Lincoln was opposed to slavery. Abolitionists felt that while he was President he didn't do enough to end the practice but Lincoln had always viewed the Civil War as being about preserving the Union. He even said "If I could free all the slaves and preserve the Union I would do that. If I could free none of the slaves and preserve the Union I would do that. If I could free some slaves and leave others is place and save the Union, I would do that also."
The fact is that from a legal standpoint the President didn't have the authority to end slavery but abolitionists had hoped that once he came into office he would immediately go to work to abolish it throughout the country.
