Every relationship is based or founded on something. For example, some relationships are based on the fact that both people work for the same company, attend the same school, or sharing a similar interest in a hobby or sport.

With all of relationships, once a common bond is no longer present, the relationship will tend to deteriorate. For example, once a child graduates from high school and moves off to college, he or she will probably lose most of the relationships formed with classmates, because school is no longer a common bond and thus there is nothing holding the relationship together.

However, if your relationships are formed around a common belief in Christ, then no matter what else happens in life, as long as that common bond is still present those relationships will last.

Thus, it is clear why 2 Corinthians 6:14 instructs believers not to marry unbelievers: Do not be yoked together with unbelievers. For what do righteousness and wickedness have in common? Or what fellowship can light have with darkness?

If you want to maintain lasting, stable relationships, they must be Christ-centered.