He who separates himself seeks his own desire, he quarrels against all sound wisdom
This seems to refer to the person who, in the midst of a team-work type of interaction, breaks away and will not consider other people’s point of view; does not want to be involved in the normal give-and-take of relationships; does not want to win some and lose some. This person wants to win every encounter with others. This is the person who will not reengage with people because it means admitting that they were wrong or selfish. They just want it their way.
This type of selfishness brings a temporary peace to their world, but it costs them dearly. If you cannot be involved in human relationships and the give-and-take that requires, then you cut yourself off from wisdom. Wisdom is about three people winning: God, others, and I.
This does not mean that you have to always be surrounded by people or you always have to give in to the demands or wishes of the group. The separation desire is usually a selfish desire and should be understood as such.
*This material is copyrighted © by Gil Stieglitz who retains all rights to the material. The verses quoted are taken from the NASB Bible 1995 edition.