The key question in the abortion debate is whether or not it ends a human life. Morally speaking, if a human being is unjustly losing their life, that is called "murder", which is not only frowned on in civilised society, but also explicitly forbidden by God. As John tells us in 1 John 3:15, no murderer has eternal life abiding in him.
Before we answer the question as to whether abortion takes a human life, we must actually take the pro-life position by default. Think of it this way: A hunter must verify his target. If you go out into the woods with a rifle, hear a rustling in the bush, pull the trigger, and subsequently find out Bambi is actually Barney, you're in serious trouble. You may have gone out intending to kill a deer, but through your negligence, you are a murderer. Therefore, even if we did not know how to answer when life begins, the pro-life position should absolutely be the default.
But scientifically speaking, we do know when life begins. From the moment of conception, a human being is demonstrably a separate human life from its mother. "But it's just a clump of cells", abortionists say. Well, first of all, this is a case of the clover calling the grass green. We're all clumps of cells. But second, that clump of cells is distinct from its parents, and is 100% human. An earlier growth stage, sure. Just as a newborn (which some abortionists are beginning to advocate killing) is earlier than a toddler than an infant than a pre-teen than a teenager than an adult. Age is irrelevant. It's not like this clump of cells will grow into something non-human, or that, left alone, it will not become a more developed human. Compare this to our sex cells individually. An egg is an egg, a sperm is a sperm, and neither of these, left to themselves, will ever become anything different.
So, scientifically, we already know that a human being is a human being from conception. From there, the case should be closed. But the imagination of abortionists knows no bounds. They believe life begins far later, and some of them, more recently, have taken to claiming that life does not begin until the baby takes its first breath. Their justification? Genesis 2:7.
Genesis 2 continues the creation account of Genesis 1, giving a more expanded view of the events of day 6. In verse 7, we read "And the Lord God formed man of the dust of the ground, and breathed into his nostrils the breath of life; and man became a living being." This, abortionists claim, proves life begins at first breath.
But given the unique origins of Adam, it is a major leap to say that since this is where Adam's life began, this is where all human life begins. Adam is actually one of only two people who did not begin his life in a womb. And you can't say that's because his life began at first breath; it's because he was never in a womb to begin with. Adam had no mother, and God is his Father. When he was first created from the dirt, he was lifeless, likely little different from a dead corpse. A mature dead corpse. Adam didn't have a childhood. Upon his creation, he was functionally mature, ready to understand complex language, work the ground, and even reproduce. Then God breathed life into him.
Adam's origins, therefore, were very unique. They had to be. The first human could not come from pre-existing humans, like all subsequent humans. Thus, it is as illogical to say that since Adam's life began at first breath, so does ours, as it is to say that since Adam was created from the dust, so are we, and since Eve came from a rib, so are all other women.
By contrast, scripture clearly speaks as if life begins at conception. It speaks about how God creates and knows us in the womb, for example. Just as God breathed life into Adam's nostrils, He knits us together in our mothers' wombs (Psalm 139:13). It is here that He gives us life, and so it's not surprising He punishes men who kill a preborn child in the same way as a murderer (Exodus 21:22-25). Nor is it shocking that there are examples of life in the womb, such as when John the Baptist "leapt for joy" at the sound of Mary's voice (Luke 1:44). Leaping for joy is a sign of life.
Of course, this should surprise no one with a basic understanding of modern medicine. Are we seriously expected to believe that 3-6 inches down the birth canal makes a blind bit of difference to a child's biological makeup? As if it spends 9 months as a formless globule, only to become human after a few hours of labor? A child is biologically identical moments before its birth as moments after. It was likely viable, especially with modern medical advances, at least 2 months earlier. It takes a very radical mind to think a child is not a living human being that late into pregnancy.
It is positively terrifying that anyone should take such a horrendous interpretation of scripture. The idea that life begins at first breath is not compatible with science, scripture, or the human conscience. Of course, we are a species that is capable of great atrocities. Some cultures heated up altars, laid their babies on top, and banged drums to drown out their dying screams. Thus, it is unsurprising that Western culture can callously ignore the silent screams of children with underdeveloped vocal chords.
But this callous ignorance of innocent bloodshed can only be forgiven with more innocent bloodshed, specifically the blood of Jesus Christ. The sin of abortion is so grievous, those who commit it are doomed to the everlasting lake of fire, where they have no rest day or night forever and ever. But in His love, God will not say "my Kingdom, my choice", but instead offers us a peace deal. Christ received our punishment on the cross so that we can receive His reward in the Kingdom of God. Therefore, repent, and believe in the risen Lord. Otherwise, He is quite within His rights to abort us.