The traditional myth of Venus and Adonis runs as follows:
Venus is with her son Cupid, and he accidentally pierces her with one of his arrows.
The next person Venus sees is the handsome youth Adonis, with whom she immediately falls in love.
He is a hunter, and she decides that in order to be with him, she will take on the form of the goddess of the hunt, Artemis.
Eventually she warns Adonis of the danger of hunting the wild boar, but he does not heed the warning, and is gored to death by the boar.

In Blow's version, Venus encourages Adonis to go hunting, despite his protestations:
Adonis:
Adonis will not hunt today:
I have already caught the noblest prey.

Venus:
No, my shepherd haste away:
Absence kindles new desire,
I would not have my lover tire.

This parallels the scene in Purcell's later Dido and Aeneas (1688), when Dido rebuffs Aeneas' offer to stay with her.
In addition to this major divergence from the myth in Adonis' motivation, Blow's version also includes the addition of a number of comic scenes with Cupid, including the spelling lesson he gives to the young cupids and his opinion that almost no one in the court is faithful—the latter an especially pungent critique given that it is believed that Cupid was played by Lady Mary Tudor, then around 10 years old and Charles II's illegitimate daughter, and Venus by Mary (Moll) Davies, the king's former lover.
The traditional myth of Venus and Adonis runs as follows:
Venus is with her son Cupid, and he accidentally pierces her with one of his arrows. The next person Venus sees is the handsome youth Adonis, with whom she immediately falls in love. He is a hunter, and she decides that in order to be with him, she will take on the form of the goddess of the hunt, Artemis. Eventually she warns Adonis of the danger of hunting the wild boar, but he does not heed the warning, and is gored to death by the boar.
In Blow's version, Venus encourages Adonis to go hunting, despite his protestations:
Adonis:
Adonis will not hunt today:
I have already caught the noblest prey.
Venus:
No, my shepherd haste away:
Absence kindles new desire,
I would not have my lover tire.
This parallels the scene in Purcell's later Dido and Aeneas (1688), when Dido rebuffs Aeneas' offer to stay with her. In addition to this major divergence from the myth in Adonis' motivation, Blow's version also includes the addition of a number of comic scenes with Cupid, including the spelling lesson he gives to the young cupids and his opinion that almost no one in the court is faithful—the latter an especially pungent critique given that it is believed that Cupid was played by Lady Mary Tudor, then around 10 years old and Charles II's illegitimate daughter, and Venus by Mary (Moll) Davies, the king's former lover.
Venus and Adonis (opera)