“For better, for worse, for richer, for poorer” is part of a Christian marriage vow. A popular riddle/joke is:
 
Q: How many wives can a man have?
A: Sixteen. Four better, four worse, four richer and four poorer.
     
Versions of the joke have been cited in print since at least 1833.
   
       
Wikipedia: Marriage vows
Marriage vows are promises each partner in a couple makes to the other during a wedding ceremony based upon Western Christian norms. They are not universal to marriage and not necessary in most legal jurisdictions. They are not even universal within Christian marriage, as Eastern Christians do not have marriage vows in their traditional wedding ceremonies.
(...)
Christianity
Roman Catholic
Couples wedding in the Roman Catholic Church essentially make the same pledge to one another. According to the Rite of Marriage (#25) the customary text in English is:
 
I, ____, take you, ____, to be my (husband/wife). I promise to be true to you in good times and in bad, in sickness and in health. I will love you and honour you all the days of my life.
 
In the United States, Catholic wedding vows may also take the following form:
 
I, ____, take you, ____, to be my lawfully wedded (husband/wife), to have and to hold, from this day forward, for better, for worse, for richer, for poorer, in sickness and in health, until death do us part.
   
October 1833, Atkinson’s Casket (Philadelphia, PA), “Wit and Sentiment,” pg. 479, col. 1:
EXPOSITION ON THE MARRIAGE SERVICE.—A Welchman had sentence of death passed upon him for having two wives, but he stormed and swore, “Uds split hur nails, hur see no reason they had to hang hur for having two wives, when the priest told hur, before a great people, hur might have sixteen:—four better, four worse, four richer, four poorer.” Instead of for better, &c.
 
Newspapers.com
23 October 1833, :The People’s Press and Wilmington Advertiser (Wilmington, NC), pg. 3, col. 4:
EXPOSITION ON THE MARRIAGE SERVICE.—A Welchman had sentence of death passed upon him for having two wives, but he stormed and swore, “Uds split hur nails, hur see no reason they had to hang hur for having two wives, when the priest told hur, before a great people, hur might have sixteen:—four better, four worse, four richer, four poorer.” Instead of for better, &c.
   
Newspapers.com
13 February 1841,
A DUTCHMAN’S DEFENCE.—A variety-loving Hollander, who had married some dozen wives, was tried in England for bigamy. “You say,” said the judge, “that the priest who married you to the first wife, authorized you to take sixteen? What do you mean by that?” “well,” said Hans, “he told me dat I should have four better, four vorser, four richer, four poorer; and in my country four dimes four always makes sixteen!”
       
Google Groups: rec.humor
VOWS
Nancy Carson
11/10/95
Susie:  “I got a new insight into marriage while I was at church last Sunday.”
Mabel:  “Yeah?  Tell me about it.”
Susie:  “Well, like everyone else, I always thought that a single marriage, you know, monogamy, was the way t go.  But not now.”
Mabel:  “Wow!”  That is a shift for you.  What did the preacher say?”
Susie:  “I heard him say distinctly, `four better, four worse, four richer, four poorer.’  That makes sixteen.”
 
Google Groups: rec.humor
(:)How Many Women Can a Man Marry?
THE BIG PIG
5/21/01
Received from Poor Innocent Guy Asa of Montgomery, Alabama:
 
How Many Women Can a Man Marry?
 
A little boy was attending his first wedding. After the service, his cousin asked him, “How many women can a man marry?”
 
“Sixteen” the boy responded.
 
His cousin was amazed that he knew the answer so quickly. “How did you know that?”
 
“Easy,” the little boy said. “All you have to do is add it up, like the preacher said: ‘Four better,  four worse,  four richer,  four poorer…’”
   
Google Groups: alt.humor.puns
Puns of the Weak 12-19-03 Part 3 The Long Puns
Stan Kegel
12/21/03
(...)
Little Johnny was attending his first wedding. After the service, his cousin asked him, “How many women can a man marry?” “Sixteen,” Little Johnny responded. His cousin was amazed that he knew the answer so quickly. “How did you know that?” “Easy,” Johnny said. “All you have to do is add it up, like the preacher said: ‘Four better, four worse, four richer, four poorer.” (Curly David)   
 
Twitter
Seven Seans A-Swimming
@ByTheMassRock
RE Teacher: How many wives can a man have.
Student: 16, Miss.
RE Teacher: 16? Please explain yourself.
Student: Well Miss, he can have four better, four worse, four richer and four poorer.
😂😂😂
4:17 PM · Jul 6, 2018·Twitter for Android
 
Twitter
Tanya Cortinaz🇲🇽🦁👑🌹
@MissLadyT2U
Two little boys are at a wedding and one of them leaned in to the other and asked
“how many wives can a man have?”
His friend answered,
“sixteen; 
four better,
four worse,
four richer and
four poorer.”
🤣😂🤣
9:17 PM · Oct 11, 2019·Twitter for iPhone