His majesty saluted his fourth spouse
With all the ceremonies of his rank,
Who clear'd her sparkling eyes and smooth'd her brows,
As suits a matron who has play'd a prank;
These must seem doubly mindful of their vows,
To save the credit of their breaking bank:
To no men are such cordial greetings given
As those whose wives have made them fit for heaven.
What is the meaning of made them fit for heaven?
Why would a cuckolded husband be "fit for heaven"?
(According to the plot, "his majesty" is a sultan who has been cuckolded by one of his wives: she ordered Don Juan bought on the slave market and brought to her in female disguise)