Translation
Did He not make one,
Go to footnote numberwith a remnant of the Spirit to Him? And why one? He is seeking Godly offspring. Therefore, be watchful and build a hedge around
Go to footnote numberyour spirit!
Go to footnote numberAnd let no man act deceitfully toward the wife of his youth. (See comment below.)
Go to footnote numberParaphrase
Did He not make [you and your wife] one [body]? Did He not put His life-giving Spirit [in both of you] so you could know Him and be like Him? And why did He make you one body? Because God is seeking a continuing series of replicas of Himself. That is why you need to watch out for situations that might compromise your soul and take steps to avoid at all costs any spiritual danger. Therefore, commit yourself to the principle that no man should ever cheat on his wife whom he has promised to love. (See comment below.)
Footnotes
1
In this discussion about men who had cheated on their wives, the reference to God making “one” is most likely a reference to the way God made man and woman “one flesh/one body,” (see Gen 2:24). It was intended as a slap in the face to the men who had violated the “one flesh” principle by sharing a bed with a woman to whom they were not married.
2
This verb comes from a root word meaning to protect by building a hedge around something, usually a hedge of thorny branches. It also acquired a strong emphasis on watching. Thus it is a picture of protection by watching out for danger and building a hedge around that which needs to be protected.
3
This Hebrew word means “spirit, soul and life.” We could render it, “guard your soul,” or “guard your spirit.”
4
The phrase “the wife of your youth” was used to point to a close, well established relationship involving strong commitments. It was much more than a statement about how long a couple had been married; instead it was a picture of a solid and healthy relationship, or one that gives every appearance of being one.
He is seeking Godly offspring
God’s desire is for us to be a reflection of Him. Then He wants us to pass on those godly traits to our children through training and example. Unfortunately, what we pass on to the next generation is a mixture of the good and the bad. Gen 5:3 says that Adam bore children in his own likeness and in his own image. In other words, he passed on his traits to the next generation, both good and bad.
Malachi 2:15 is highlighting the desire of God for us to train our children to not only follow Him, but also to be a reflection of who He is and what He is like. In order to do that we need to treat marriage with the seriousness He intended. There is no room for any sexual immorality.