Ok so a few things to unpack here.
First things first, this is a question that needs answering in the context of marriage. It’s one of the things that when you are married, or even better when you are approaching mariage, that you sit down and talk through with your wife. You need God's word to be your guide here, but I’m going to give you a few principles that are in God's word here.
Sometimes we’re taught that contraception or forms of it are a way to experience human sexuality outside of that context of marriage, and not suffer any consequences. They will protect you from STDs as well as prevent the supposed inconvenience of having a child in your life. These aren’t good reasons to use contraception.
Proverbs 6:32 But whoso committeth adultery with a woman lacketh understanding: he that doeth it destroyeth his own soul. 33 A wound and dishonour shall he get; and his reproach shall not be wiped away.
Any form of sexuality outside of the context of biblically defined marriage is wrong and will come with consequences for you. And this can be as simple as looking at a female who you aren’t married to with desire.
Matthew 5:28 But I say unto you, That whosoever looketh on a woman to lust after her hath committed adultery with her already in his heart.
So with that said, we’ll look at the answer to the question within the context of marriage.
Modern contraception isn’t found in the bible.
The closest we get to it is the story of Onan found in Genesis.
Genesis38:8 And Judah said unto Onan, Go in unto thy brother's wife, and marry her, and raise up seed to thy brother. 9 And Onan knew that the seed should not be his; and it came to pass, when he went in unto his brother's wife, that he spilled it on the ground, lest that he should give seed to his brother. 10 And the thing which he did displeased the Lord: wherefore he slew him also.
Now when finding a principle, scripture should agree with scripture, so given this is the only verse that comes close to mentioning contraception, we should be careful if we’re trying to make a principle from it.
Where this passage does match up with scripture is that what he did was selfish. He used her for his own sexual gratification, but didn’t want to raise a child that would be for his brother, and not his. We don’t have the same practice today, but there are modern day equivalents that we could apply the same principle to. If you marry someone who already has a child who isn’t yours, and you are selfish and won’t spend your time, money and effort on that child, then that is wrong. We’re called to love our neighbor as ourselves and the bible contains special warnings for those who offend against little ones.
So there aren’t any direct verses condemning or condoning contraception.
Why would we not take contraception?
Ultimately children are an amazing thing. I’m not gonna lie, they are a load of hard work, and hard work that you can’t give up for the next 20-30 years. And they force you to change. If you are lazy, it’s not going to work that well with children. If you are impatient, it’s not going to work that well with children. If you are selfish, again it’s not going to work that well with children.
But all that said, God tells us that:
Psalm 127:3 Lo, children are an heritage of the LORD: and the fruit of the womb is his reward.
Children are a reward of God, and God calls us to multiply.
We’re encouraged to have children, and there are a number of promises and pictures in the bible related to children.
Children inconveniencing my lifestyle I don’t think is a good reason.
Why would we take contraception?
Health reasons, such as risk to a mother. I’ve heard a story of a husband being told that his wife was at risk of dying if she got pregnant again. His view was that it would be in Gods hands. She got pregnant, and ended up losing her life. This is a bad example of not loving your wife as yourself and tempting God.
If there is a risk to your wife, then you should consider contraception. This could be both physical risk to her, or emotional risk. You need wisdom here.
Another reason could be you have a calling from the Lord that having children wouldn’t be wise. If you believed that you were called to be a missionary in a country where there was a high chance of dying and leaving your children without parents, then you may choose again to not have children. Again this is something that requires wisdom and guidance and prayer.
You may also not be in a position to be able to care for children.
I’m not saying that there is a reason where you must have children, or you must not have children. Just that it is for each married couple to talk through, have counsel where helpful, but most of all look to God and His word for what to do.
What principles do we have if taking contraception?
First one is:
Exodus 20:13 Thou shalt not kill.
Don't choose a contraceptive that would cause you to kill an unborn child. Life begins when an egg is fertilised. Many in this world won’t see it that way, which is why we have the option to have abortions, but Gods word teaches that we are alive and God is working in us while in the womb.
Jeremiah 1:5 Before I formed thee in the belly I knew thee; and before thou camest forth out of the womb I sanctified thee, and I ordained thee a prophet unto the nations.
No contraception will perfectly remove any chance of pregnancy, but some will increase the chance that a fertilised egg has less chance to grow. Some for example thin the lining of the uterus leading to a decreased chance of a fertilised egg being able to implant itself into the uterus, and ultimately cause the baby to die.
Second one is:
Our bodies are there to be taken care of
19 Do you not know that your bodies are temples of the Holy Spirit, who is in you, whom you have received from God? You are not your own; 20 you were bought at a price. Therefore honor God with your bodies.
We believe that we’re to take care of our bodies. This is why we wouldn’t smoke or vape, and why we would exercise.
Look at side effects of any contraception you are considering. Some will come with side effects, for example increased blood pressure, and some linked to cancer. You can find this information on the NHS website.
We as men are to care for our wives, and make sure we are looking after them. We shouldn’t be putting them under pressure to take something that could be bad for them.
Ephesians 5:28 So ought men to love their wives as their own bodies. He that loveth his wife loveth himself.
Third is:
What works for you. Some contraception requires a lot more effort or control than others. Some you may have a personal preference against. When the first 2 reasons are ticked off, then this should be a consideration.
So to sumarise, having children is a wonderful thing and a blessing, but you need to consider whether there are reasons why you wouldn’t have children. Have this discussion before getting married, as it could cause a lot of conflict when one goes into marriage expecting to have children and the other goes in expecting not to. If you do believe that for a period or even permanently you shouldn’t have children, or any more children, then consider the impact of particular types of contraceptives, and chose the one that you believe most closely aligns with Gods word. Remember no type of contraception is 100% perfect, so there is still a chance of having children no matter what.
If you want more detail on this topic, I recommend the book “Intended for pleasure by Ed and Gaye Wheat. It has a whole chapter on contraception, and goes into detail on the various types of contraception, how they work and their advantages and disadvantages, as well as chances of still conceiving when taking that type of contraception.