Again, ye have heard that it hath been said by them of old time, Thou shalt not forswear thyself, but shalt perform unto the Lord thine oaths:
But I say unto you, Swear not at all […]
But let your communication be, Yea, yea; Nay, nay: for whatsoever is more than these cometh of evil. (Matthew 5)
I didn’t know what to make of this when I originally read it. It seemed peculiar, and an outlier of what Jesus is saying in other parts of the Sermon on the Mount. I did not see the import of it. Yet, Emmet Fox reverses that. He says (The Sermon on the Mount, p. 68-70)
Swear not at all is one of the cardinal points in the teaching of Jesus. It means, briefly, that you are not to take vows. You are not to mortgage your future conduct in advance; to undertake to do or to refrain from doing something tomorrow, or next year, or thirty years hence.
This is striking, because Fox claims this is not peripheral but cardinal. Why would ‘not taking vows’ be central to Jesus’ thought? As he continues,
It is an absolutely vital part of [Jesus’] teaching that you are constantly to seek direct inspirational contact with God, constantly to keep yourself an open channel for the pouring out of the Holy Spirit into manifestation through you. Now, if you make up your mind in advance as to what you shall do or shall not do, shall believe of shall not believe, shall think or shall not think, shall be or shall not be, tomorrow, or next year, or for the rest of your life – and especially when you crystallize this determination by a solemn act of the will like a vow – you are not leaving yourself open to the action of the Paraclete; but you are, by that very act, shutting him out. If you are to receive the guidance of God, Divine Wisdom, it is absolutely essential that you have an open mind, because it so often happens that the part of wisdom is not in accord with your own personal feelings or present opinions. But if you have taken a vow or made a promise concerning your soul, for tomorrow, you are no longer uncommitted; and unless you are uncommitted, the action of the Holy Spirit cannot take place. This, in fact, is nothing less than the sin against the Holy Ghost of which the Bible speaks, which has caused so much terror to sensitive hearts, and concerning which there seems to be a very general misunderstanding.
What is the sin against the Holy Ghost? The sin against the Holy Ghost is any action on your part which prevents the activity of the Holy Ghost from taking place in your soul; anything which shuts you off from the ever-fresh energizing action of God that is spiritual life itself. The penalty for this mistake is spiritual stagnation and, since the only remedy in such a case consists in the direction action of the Holy Spirit, and this mistake in itself tends to prevent that very action from taking place, a condition of vicious deadlock results. Now it is obvious that this condition must necessarily remain as long as the mistake is persisted in, and so, in this sense, the sin is unforgivable. The problem cannot be solved in any way until the victim is prepared to change his attitude. The symptoms of this malady are spiritual stagnation, and all-round failure to demonstrate [(i.e., concrete results of God’s actions in one’s life)], and these are only too often accompanied by much self-righteousness and spiritual pride.
So Fox takes something that seems peripheral (‘don’t make vows’), and then interprets it in light of something central to Jesus’ thought (one should aim to be in constant, live contact with God). This is the right way to do Scriptural exegesis in general – to throw light on what seems incongruous or irrelevant in terms of what is known to be central. In this sense, the odd claim to not make vows can be seen as an application of a central part of Jesus’ thought (be open to God’s Wisdom, and do His will).
Furthermore, Fox then extends that to making sense of another, seemingly singular and confounding claim Jesus makes about a ‘sin against the Holy Spirit’, which is a natural implication of the point about making vows!
To conclude, Fox then draws the obvious conclusion if this is the correct interpretation – Jesus didn’t mean to not enter into everyday business contracts and so on.
Of course, Jesus does not mean that you are not to enter into ordinary business engagements, such as taking up the lease of a house, signing an agreement for certain services, entering into partnership, and so on. Nor does he mean that the ordinary oath administered in a court of law is inadmissable. These things are matters of legal convenience for the transaction of business between man and man, and they are right and necessary in an ordered society. The Sermon on the Mount, as we have seen, is a treatise on the spiritual life, for the spiritual controls all the rest. One who understands the spiritual teaching of Jesus, and practices it, will be in no danger of breaking honorable agreements. He will be an ideal tenant, a desirable business partner, and a reliable witness in court.
In other words, the superficial and tempting interpretation is almost the opposite of what is meant, just as a material interpretation of, say, the second Lukean beatitude (‘blessed are the hungry’) isn’t at all the proper sense (rather, ‘blessed are those who hunger for righteousness’, the key being given in this case from Matthew, a completely different idea).