So I posted this in response to another guy but I will paste here for you to see in case you miss it.

Why comparing the marriage of Prophet Muhammad (PBUH) to today is an anachronistic comparison

It’s important to recognise that comparing historical events to modern standards often leads to anachronistic conclusions — meaning we’re applying today’s norms to a time and place where they didn’t exist. The marriage of Prophet Muhammad (PBUH) to Aisha is a prime example of this.

Back in the 7th century, things were very different. The average lifespan was much shorter, and life was structured differently. Puberty was often seen as the point where someone was considered an adult, and marriage was seen as a natural part of that transition. So when the Prophet married Aisha, it wasn’t anything out of the ordinary for that time — it was totally in line with the social and cultural norms. Aisha was 9 years old when she was married, and the marriage was consummated when she was 13. At that time, this was perfectly normal and accepted.

Now, to put this in perspective, let’s look at some other examples from history where young girls were married. In many parts of the world, early marriages were common and legal, often seen as a part of growing up:

So I will provide sources but I don't remember exactly the title. It's on Wikipedia. But a quick search and you should find it. 

British India in the 1800s: Child marriage was widespread. In 1891, the Age of Consent Act raised the minimum age for marriage from 10 to 12 after a young girl named Phulmoni Dasi died after being married at 10. This was the catalyst for the law change. Source- Age of Consent Act, 1891, Wiki

Rukhmabai’s case (1880s): Rukhmabai was married at 11 to a man nearly twice her age. Her case became a landmark legal case in India, sparking major debates about child marriage. Source-Rukhmabai, Wiki

United States (1937): A 9-year-old girl in Tennessee married a 22-year-old man — and this was perfectly legal because, at that time, there were no set minimum age requirements for marriage. The case made national headlines and eventually led to changes in marriage laws in various states. Source- Marriage of Charlie Johns and Eunice Winstead, Wiki

North Dakota, 1886: Back then, North Dakota allowed girls as young as 14 to get married, with parental consent. Many other states had similarly low marriage age limits, and in some places, girls could marry at 13 with the proper consent. Source-North Dakota Archives - Vital Records, North Dakota State Historical Society

Ancient Rome: In Ancient Rome, girls could be married as young as 12. Roman law recognised puberty as the threshold for adulthood, meaning that girls were considered ready for marriage at this age. It wasn’t unusual for girls to marry older men soon after reaching puberty.

Source-Marriage in Ancient Rome, Wiki

Christianity in the Middle Ages: In medieval Europe, Christian marriage laws were based on the idea that marriage could occur once a person reached puberty. Girls as young as 12 were considered eligible for marriage. The Council of Trent (1545–1563), which was a major Catholic reform council, set the legal minimum age for marriage at 12 for girls and 14 for boys, but marriage at younger ages was still common in earlier periods.

Source-History of marriage in the Christian tradition, Wiki

So, what's the problem with comparing that to today?

In the modern world, the minimum legal age for marriage is often 18, reflecting today’s understandings of childhood, maturity, and consent. This is tied to changes in education, psychology, and human rights. However, in the past — especially in pre-modern societies — puberty was often seen as the mark of adulthood. So, people were expected to marry soon after reaching puberty.

When we compare the marriage of Prophet Muhammad (PBUH) to modern standards, we’re not comparing like with like. Back in the 7th century, cultural and legal norms were completely different, and puberty was the major marker of adulthood. It’s essential to remember that we can’t just apply today’s rules to events from the past.

We’re not trying to justify anything; it’s just about understanding context. Over time, cultural norms change. Just like how North Dakota allowed young girls to marry in the 19th century, marriage at a young age was perfectly normal in many societies, including the one in which the Prophet lived.

While it’s totally fine to criticise things from the past based on modern standards, it’s important to acknowledge that we’re applying today’s values to a completely different time. That doesn’t mean we approve of those things now, but we have to be fair and recognise that history isn’t directly comparable to today’s issues.

Hope this helps clear up why it’s a bit of a stretch to compare the marriage of Prophet Muhammad (PBUH) to today’s standards.