Here's a breakdown of Blake's critique:
Church:
* "Marks of weakness, marks of woe": Blake sees the Church as a symbol of hypocrisy and inaction. Instead of offering solace and hope, it seems to reflect the suffering of the people.
* "In every cry of every man, In every infant's cry of fear": The Church's supposed moral authority is undermined by the widespread poverty and fear Blake sees. It fails to address the real needs of the people.
* "The mind-forg'd manacles I hear": Blake suggests the Church contributes to a form of spiritual enslavement, where people are bound by dogma and fear, unable to think freely.
Palace:
* "And the hapless soldier's sigh Runs in blood down palace walls": The Palace, representing the ruling class, is associated with violence and indifference. The blood of soldiers (possibly reflecting war or oppression) stains the walls, symbolizing the cost of their power.
* "The youthful harlot's curse": The Palace is linked to the exploitation of young women, highlighting the corrupt and immoral nature of the powerful.
* "Blasts the new-born infant's tear": The Palace is responsible for creating a world where even innocent children experience hardship and despair.
Overall:
Blake paints a picture of a society where both religious and political institutions are corrupt and contribute to the misery of the people. He criticizes the Church for its lack of action and its role in enforcing social control, while he condemns the Palace for its cruelty and exploitation. "London" is a powerful indictment of the injustices and suffering he sees in his time.