You’ve most likely read or heard about Paul’s illustration of how the church is the body of Christ. We are the body which, while made up of many parts, is one. While it is one, it has many members. The problem that Paul sees in the church is that some parts are thinking of themselves as lesser than others (or being made to feel as though they are less). Paul writes in 1 Corinthians 12:
For the body does not consist of one member but of many. If the foot should say, “Because I am not a hand, I do not belong to the body,” that would not make it any less a part of the body. And if the ear should say, “Because I am not an eye, I do not belong to the body,” that would not make it any less a part of the body. If the whole body were an eye, where would be the sense of hearing? If the whole body were an ear, where would be the sense of smell? But as it is, God arranged the members in the body, each one of them, as he chose. If all were a single member, where would the body be? As it is, there are many parts, yet one body.
His illustration makes sense to us without any further cultural insights, but his point is even stronger when we learn how certain body parts were viewed. His example of a foot is not chosen randomly. The foot, being the very bottom of the body, was (and still is in some cultures in the Middle East) seen as dishonorable. It would be offensive to show the sole of your foot to someone if you were to travel to certain countries. So what Paul is doing here is picking the part of the body that would most likely be seen as a lesser part and using it as the example of that which should be kept in high esteem.
But God has so composed the body, giving greater honor to the part that lacked it, that there may be no division in the body, but that the members may have the same care for one another.
Using the foot Paul makes his point that even those that may be seen as the lowest should be valued in the church body. There is no exception. The body is one and should live with unity, not stratification or divisions.