God’s Word for You

Philippians 1:8 An oath

by Pastor Timothy Smith on Thursday, February 12, 2026

8 For God is my witness, how I long for all of you with the affection of Christ Jesus.

To call upon God as a witness is a form of taking an oath, which might bring readers into the question of how we keep the Second Commandment. Before we touch on that, we want to understand what Paul is swearing about, which is his longing for the Philippians with the same affection that Christ showed to his followers and to the world (Luke 13:34-35). This affection of Jesus is often described with the Greek word splanchnon (σπλάγχνον), a word that grabs at the guts and heart and describes one’s inmost feelings, a gut-wrenching compassion and affection. Strictly speaking, the Greek word corresponds to the Latin viscera or “nobler viscera,” which is to say the heart, liver, lungs, spleen, and so on, as opposed to the bowels. It was considered by the Greeks to be the seat of emotions: affection, anger, love, pity, jealousy, and so on. Here it is a yearning, a heartache, a love that willingly endures pain for the sake of the one who is loved. Paul said about the runaway slave Onesimus, “He is my very splanchna, my very heart, and I am sending him back to you” (Philemon 1:12). Such an emotion is possible in either the godly or the wicked, but “the kindest acts (splachna) of the wicked are cruel” (Proverbs 12:10) because they are not done out of faith. “A fool’s affection spins around like a wagon wheel” (Sirach 33:5).

But the affection of Christ is the longing that brings us to pray for one another’s needs, health, safety, well-being, success, and faith. It makes our most profound yearning be for one another’s soul. It is “the compassionate mercy of our God” (Luke 1:78), and the “affection and sympathy” of Philippians 2:1. Paul urges the Colossians to clothe themselves with such “compassion and kindness” along with humility, gentleness, and patience (Colossians 3:12). The immediate application of this is “to bear with one another, and forgive whatever complaints you may have against each other. As the Lord forgave you, you should do the same” (Colossians 3:13).

Why does Paul swear an oath with this affection? A godly oath is sworn to assure someone that we are telling the truth. “The high priest said to Jesus, ‘I put you under oath to the living God, tell us if you are the Christ, the Son of God.’ Jesus said to him, ‘You yourself have said it. But I tell you, after this you will see the Son of man seated at the right hand of Power, and coming on the clouds of heaven’” (Matthew 26:63-64). And in Hebrews we are told, “Men swear by someone greater than themselves, and the oath confirms what is said and puts an end to all argument. Because God wanted to make the unchanging nature of his purpose very clear to the heirs of what was promised, he confirmed it with an oath” (Hebrews 6:16-17). And the Lord God swears by his own name in Moses and in the prophets (Genesis 22:16; Isaiah 45:23 Jeremiah 22:5, 44:26, 49:13).

One ancient pastor thought that Paul swears here “not as one who has a lack of trust and confidence that he calls upon God as a witness, but he does so from his great exuberance of spirit.” But we should remember that this is a prison epistle (1:7,13-14). Paul had no way to show or prove his compassionate longing for the Philippians; no smile that they could see, no tone in his voice that they could hear, no firm grip on the shoulder that they could feel, and so he used the one means of communication open to him. He swore honestly and truthfully that this was his feeling for them. It was, because there was no other possibility, a necessary oath.

It would be best for God’s rational creatures to become so accustomed to telling the truth that our plain speech would take on the character of an oath. And there is an old saying, “To swear rightly is to navigate a difficult course.” When a man develops the habit of swearing often, it is sadly a sure sign that he is not trustworthy at all. And there is a wise saying in the apocrypha: “Do not accustom your mouth to oaths, nor habitually utter the name of the Holy One; for as a servant who is constantly under scrutiny will not lack bruises, so also the person who always swears and utters the Name will never be cleansed from sin. The one who swears many oaths is full of iniquity, and the scourge will not leave his house” (Sirach 23:9-11).

So, should we give a list of oaths that are okay to swear? Should we say that we swear an oath at Confirmation, and in marriage, and in a courtroom, or military service, when we accept a divine call, or when we are installed into a political office? Shouldn’t we say that even at these times, we need to search our hearts? Are we indeed telling the truth, and swearing to it? Or are we deceiving people and trying to pull the wool over God’s eyes while we do it?

Another way of looking at swearing oaths is this: Private oaths should be few and far between. Most people should go a lifetime without needing or wanting to swear an oath in private.

Public oaths, solemnly taken in a public place (a church or a courtroom) may be necessary, but should be sworn with an honest heart and without any deceit.

An oath that asserts something or denies something about a present or past thing could be done either in private or in public.

A voluntary oath is self-explanatory, and is generally sworn (such as in court or in church) by those with a clear conscience.

Its opposite is a compulsory oath, when someone is forced to swear unwillingly. This might be done in court by a guilty party, or it might be done when a tyrant or a dictator asserts himself in a cruel way. On August 2, 1934, this happened in Nazi Germany when Hitler forced the army and navy to swear loyalty not to the German constitution but to him, personally, by name, trapping them into unconditional obedience (the “Führer Oath”). This is also described as an alien or imposed oath because it does not come from the heart of the one who takes it.

Jesus Christ our Lord teaches that it is idolatry to swear by anything created, whether a creature or an object. “Do not swear at all: either by heaven, for it is God’s throne; or by the earth, for it is his footstool; or by Jerusalem, for it is the city of the Great King. And do not swear by your head, for you cannot make even one hair white or black” (Matthew 5:34-36). And in the prophets there are many statements like this. “Your children have abandoned me and sworn by gods that are not gods” (Jeremiah 5:7). And again, “They worship by swearing to the Lord, and yet they also swear by Molech” (Zephaniah 1:5). And again, “The strong and mighty will faint and be brought low because they swear by the shame of Samaria” (Amos 8:12). Joshua said simply and with God’s authority: “Do not associate with these nations that remain among you; do not invoke the names of their gods or swear by them. You must not serve them or bow down to them. But you are to hold fast to the LORD your God” (Joshua 23:7-8). Those who swear by God’s name should do so to praise him (Psalm 63:11).

God’s name has been given to mankind so that we will know him, so that we will give him glory and praise, so that we may proclaim, teach, and preach about him and how he has brought us salvation, and so that we can pray to him and give him thanks. This is summarized in the Catechism with Luther’s brief words: “Pray, praise, and give thanks.” This is how his name is made holy.

In Christ,
Pastor Timothy Smith

 

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