Because the church as a whole encourages young marriage for a few reasons, some spiritual and some practical. I’m speaking from the perspective of someone who was raised in a very traditional Pentecostal church. A lot of what I say can translate to other denominations also but they may not be as strict as what I grew up on.
1. COURTSHIP “POLICY”: The longer you date or court someone is the more likely that you will engage in sexual activity before marriage…a sin known as FORNICATION!! It’s very normal for a couple to literally date for only 6 months and the pastor will give them the green light to get married. That seems unheard of but it’s VERY common in the traditional church! Long courtships are STRONGLY discouraged!