What the Bible says about Companion
(From Forerunner Commentary)
Companionship has the benefit of producing strength. In unity, there is strength. In these proverbs given in verses 9-12, he means not only, for example, is there help in companionship for somebody who literally falls in a ditch (verse 10), but also, if somebody makes a mistake, a companion can cover it and maybe help him out so that the error does not hurt him so badly. Companionship gives strength because a companion can offer so much help.
John W. Ritenbaugh
Ecclesiastes and the Feast of Tabernacles (Part 2)