In this poem, the narrator addresses his mistress, and pleads with her to go on one last ride (on horses) with him. The "ride" is literally a ride on horseback but "ride" also has sexual connotations. His mistress, his beloved, has rejected him or at least does not love him. He is upset at being rejected but he's determined to make the most of this one last ride. The poem begins with the speaker asking for one last ride, continues with the ride itself, and it ends with him dreaming about the ride lasting forever.
The ride begins in the fourth stanza. The speaker leaves all rejection and past failures behind him. He just focuses on enjoying the present moment with her:
Past hopes already lay behind.
What need to strive with a life awry?
Had I said that, had I done this,
So might I gain, so might I miss.
The speaker goes on comparing his success (the ride with his beloved) with the successes of others. He claims that, even though she does not return his love, his success in having this one last ride with her is better than successes in other parts of life:
There's many a crown for who can reach.
Ten lines, a statesman's life in each!
The flag stuck on a heap of bones,
A soldier's doing! what atones?
They scratch his name on the Abbey stones.
My riding is better, by their leave.
The speaker finds the joy in riding with her more sublime than a poet's descriptions. He finds more substance in the ride than the sculptor finds in Art and more than the musician finds in music. The speaker rationalizes further, noting that if he possessed his beloved fully (she returning his love absolutely) then Heaven would be a step down. Therefore, the speaker supposes that he necessarily can't fully have her because such a notion would be so sublime it could only occur in Heaven:
Earth being so good, would Heaven seem best?
Now, Heaven and she are beyond this ride.
In the last stanza, the speaker dreams of the ride lasting forever, thus becoming like a heaven on earth, "The instant made eternity."