By inference/induction/deduction, we could definitely know that ( 2 Corinthians 6:14 )'s use of "yoked"/ "bound" / "close association" certainly at the very least refers to marriage. Let's just reason it out:
-If a Christian person has a professional business relationship with a NonChristian, he/she can say that it's debatable if one tries to characterize said relationship with terms like "yoked"/ "bound" / "close association" because it's merely a professional work-related business transaction for making money.
-If a Christan person participates in a team-based sports game(i.e football, basketball, etc.) with NonChristian team members, he/she can say that it's debatable if one tries to characterize said relationship with terms like "yoked"/ "bound" / "close association" because it's merely an event involving jovial/recreational activities.
-However, The strongest type of human-to-human relationship that can definitely be associated with terms like "yoked"/ "bound" / "close association" is marriage. The reason being is that we can infer/induce/deduce that marriage involves the closest & most intimate human-to-human relationship between a man and woman because they are so "yoked"/"bound" spiritually, mentally, emotionally,etc., to each other. Furthermore, we can even say that the man and woman become one in marriage based on the following verses by employing "scripture interprets scripture" hermeneutic which definitely can be characterized as "yoked"/ "bound" / "close association" relationship.
Marriage is the strongest type of human-to-human relationship that can definitely be associated with terms like "yoked"/ "bound" / "close association"? (In other words, we can infer/induct/deduce that 2 Corinthians 6:14 can certainly at the very least be referring to marriage because marriage is the most "yoked" / "bounded" / "closely associated" human-to-human relationship in this world. But, other relationships like manager-employee, etc, are less intimate