"Uphill" can be read as an allegorical journey of life and death, particularly because of Rossetti's own faith. Her Protestant views can be interpreted through various symbols in this poem, including the "door" at which the traveler arrives.

The traveler in this poem is on a difficult journey that constantly goes uphill; this reflects the difficulties in life, which cause the traveler to grow increasingly fatigued as the journey nears its completion. There is the promise of a "resting-place" when night comes, which is frequently symbolic of death. There are two presumed speakers in this poem: one who asks questions and another who answers. The first speaker questions whether she should knock upon arriving at this "resting-place." Christians will recognize the usage of "knocking" as it is used in several places in the New Testament to describe the process of salvation:

So I say to you: Ask and it will be given to you; seek and you will find; knock and the door will be opened to you.
(Luke 11:9)

Be like men who are waiting for their master to come home from the wedding feast, so that they may open the door to him at once when he comes and knocks. (Luke 12:36)

Ask, and it will be given to you; seek, and you will find; knock, and it will be opened to you.
(Matthew 7:7)

Salvation is given to anyone who "knocks," or asks. Likewise, the first speaker is told that she will not have to wait long "standing at that door." The host is waiting for her arrival and has been preparing for the "sum" of her life's labors, much as God is waiting to welcome those who have believed and asked for salvation.