It is written: "Man goes out to his work and to his labor (Avoda) until evening." [Tehillim / Psalms Tehillim 104:23]
Every soul in its descent into this material world has general and personal tasks. This, then, is the meaning of the verse:
On a more profound level the verse may be explained as follows:
The verse refers to the ascent of the soul in general, achieved by its prior descent (Man goes out) into the material world:
When the soul ascends from its being enclothed in the body in this material world, then...
...to his work - the soul's occupation in the World To Come is commensurate with its occupation in the material world.
If he had studied Torah regularly, there too (in the World To Come) the soul is ushered into the "Tents of Torah";
...to his labor - if he performed his Avoda properly then his ascent goes on...
...until erev ("evening") - higher and higher until he attains the ultimate delight and Areivut ("sweetness") of the Essence of the En Sof (The Infinite), may He be blessed.