Being equally yoked is an interesting discussion because it relates to Christian Camaraderie. First it comes from 2 Corinthians 6:14 - "Be ye not unequally yoked together with unbelievers: for what fellowship hath righteousness with unrighteousness? and what communion hath light with darkness?" (KJV). A yoke was a harness for 2 beasts of burden (Oxen, Horses, Mules, etc) to be "yoked" side-by-side so they could pull together. Without a yoke it is very difficult to make them pull together and you wanted to make sure that you put (2) beasts together that were about the same strength and size so that they were "equally yoked". The meaning of the parable has to do with surrounding ourselves with people who have the same strength in testimony, faith, and belief. By doing this, we strengthen each other and make it possible to face challenging things even easier.
It is so important to surround ourselves with people who build us up and strengthen us! How can we strive from this?