Wow, this is a really big topic, and in the short space of this context I really cannot hope to layout all the issues and nuances of this important issue. But I will attempt to outline a few of the basic principles that
The term"Drugs" is used to cover a wide range of substances including antibiotics, aspirin, alcohol, caffeine, tobacco as well as illegal drugs such as cocaine, speed & marijuana. While there are a number of references to alcohol, there is nothing explicit about many of the other substances. Nonetheless there is sufficient instruction in the Bible so that follower of Jesus can determine how to think about the general topic of"drugs".
First, drugs are a part of God’s good creation, provided by God as a part of his plans and purposes to ‘equip’ creation to be a place of blessing. There is nothing wrong with"drugs" in and of themselves. Used correctly drugs can be useful and beneficial to humanity. For example, one writer in the Bible [in Psalm 104:14-15] says:
[God] makes grass grow for the cattle,
Second, problems with"drugs" arise when they are misused - it is not drugs, but drug abuse that is wrong. For example, following through the theme of alcohol, the apostle Paul encourages the followers of Jesus in Ephesians 5:18:
Do not get drunk on wine, which leads to debauchery. Instead, be filled with the Spirit.
There are two other principles need to be taken into consideration with this issue.
Followers of Jesus are encouraged to submit to the laws and authorities of the societies in which they live (Romans 13:1-5). The Bible recognises the authority of governments as given by God, for the purpose of the good ordering of society. As such, Christians should seek to, wherever possible, submit to the rules and regulations set by governments. Thus, if a government, in its wisdom, determines certain guidelines for the use of specific drugs, (for example, that marijuana is ‘illegal’) then Christians should respect the authority and decision of the government and obey that law.
Followers of Jesus need to consider the effects of their actions on others, both in direct consequence and by the example of behaviour that is set. For example, consider a Christian deciding whether to having a glass on wine with their dinner. One glass probably won’t get them drunk, and if they are over 18, then they are legally allowed to have it. But they also need to consider if having the glass of wine would be unhelpful for others - if they were having a recovering alcoholic over for dinner, then having the glass of wine would be unhelpful for the guest - and so the Christian should abstain for the good of the alcoholic. The thinking should not be simply what I can do, but what is the loving thing to do for others.
These are priniciples that help us to work out how to live in the specifics of our day to day living. We need to be wise as we make decisions and this wisdom comes from God (James 1). So let me encourage you to read the bble and understand these (and the other) biblical principles of living and then ask God to help you wisely decide how to live.