Where Is the Poetry?

Abu al-'Ala' al-Ma'arri wrote to one of his friends, excusing himself from attending a certain gathering and proposing another. He did not intend to compose verse — yet what he sent is four lines of poetry. How, then, would you divide it up so that it falls into a single meter and a single rhyme?

"May God keep you in health and preserve you. You ought to have come to us today at our present dwelling, so that your companionship might converse with us, O ornament of friends; for none like you has ever altered a pledge or exchanged it!"