But he that is greatest among you shall be your servant. Matthew 23:11 KJV https://bible.com/bible/1/mat.23.11.KJV

This verse doesn’t endorse being a slave or any other type of servitude in which a person could be used as a slave. It merely states that in your walk with Jesus daily you should learn to have a servant’s attitude. Read the gospels and the Psalms and you can understand what type of attitude this actually is because it is expressed in the New Testament when scripture says “if you are compelled to go with someone for a mile, go with them two miles“. Jesus taught this when He was preaching to the crowd on the mountain. His sermon on the mount is the best sermon that you will find in the New Testament.