past

• The Ghost of Christmas Past is an interesting vision – it changes shape and size, it has many arms and then a few, it seems distant and close, old and young – in fact it seems riddled with contradictory images. In many ways the vision works like memory can do: it changes depending on perspectives or moods. It's also interesting that the ghost is described as having strong arms and hands "as if its hold were of uncommon strength." This is a great description of the ghost as a memory, because memories - as Scrooge is about to learn - can exert an uncommonly powerful hold over us.  
•  Visually, the ghost appears as a candle - the shot of light from its head, while its outfit is a square of white cloth (it even wanders around holding a candle snuffer that looks like a hat.) Seeing it as a candle also helps its role as representing memories as phrases like “holding a candle” for someone mean to remember them, while candles are used in churches to remember those who've passed on. 
• Also, Scrooge finishes the stave by putting out the candle, which shows him symbolically putting down his past – leaving behind the resentment he has harboured at having lost his childhood to neglect. In this way, like a patient completing therapy, he has faced his past, but can now move on.
• Alongside this, however, you could argue that this creature, who appears to be both young and old, is an image of Jesus – who was a baby at Christmas and yet who, as the son of God, represents the divine wisdom that Christians worship. The most clearly religious image though is how it wears a “tunic of purest white,” as though it is a pure, innocent Angel sent to guide him.