A Biblical Look
The biblical criterion for "meaningful life" (a phrase so dear to pro-abortionists) is the possession of the spirit in man (I Cor. 2:11). By this theological criterion, a "blob of cells," even if it doesn't seem human, is human if it has the spirit in man. The next question is, naturally, when does the spirit in man enter into a human being?
We cannot say for sure. There are two admittedly vague biblical indications: the various references to the "breath of life" (e.g., Gen. 2:7) and the reference to the "life being in the blood" (e.g., Lev. 17:11). The former strengthens, though does not prove, the pro-abortion argument, while the latter, if applicable to the fetus, would positively disprove it. However, one can counter on both sides that such phrases only serve literary or poetic purposes, and are not philosophical statements which could apply one way or the other. So we must look elsewhere.
It is undeniable that metaphorically Bible writers speak of fetuses as individual persons. Psalms 139 is perhaps the most striking: "For thou hast possessed my reins: thou hast covered me in my mother's womb. I will praise thee; for I am fearfully and wonderfully made: marvelous are thy works; and that my soul knoweth right well. My substance was not hid from thee, when I was made in secret, and curiously wrought in the lowest parts of the earth. Thine eyes did see my substance, yet being imperfect; and in thy book all my members were written, which in continuance were fashioned, when as yet there was none of them" (verses 13-16).
The phrase "the lowest parts of the earth" is recognized by many commentators as a biblical metaphor for the womb. This passage is poetic, but there is no denying that in the course of this poetry the psalmist imputes, by the use of the pronoun "me," individual personality to himself while yet unborn.
The phrase "in thy book all my members were written" at the very least shows that God takes notice of the individuality of the fetus, and we certainly cannot categorically rule out the possibility that God does indeed ascribe a personality to the fetus, a personal individuality which God remembers (possibly in His "book"?). And since we cannot rule this out, it invalidates the pro-abortion argument that the aborted fetus could not be human because it could not be resurrected.
Jeremiah's case is perhaps less poetic, more straightforward. He wrote that God told him: "Before I formed thee in the belly I knew thee; and before thou earnest forth out of the womb I sanctified thee . . ." (Jer. 1:5).
The imputation of personality to the fetus of Jeremiah in this passage is clear, and there is no way of proving that God did not begin to ascribe such personality from the moment of conception.
Isaiah said that "from the womb, from the body of my mother he [God] named my name" (Isa. 49:1, RSV). Again, God treats a fetus as a separate, distinct personality, even with its own name, before birth.
In chapters 25 and 38 of Genesis, unborn children, in each case twins, are ascribed individual differences so much that they already, before birth, symbolize character traits in the various nations which would eventually become their progeny.
And Ecclesiastes 11:5 is particularly interesting. The Living Bible translates the passage: "God's ways are as mysterious as the pathway of the wind, and as the manner in which a human spirit is infused into the little body of a baby while it is yet in its mother's womb." While this seems to be a definitive antiabortion scripture, it could be argued that The Living Bible is far too loose in its translation. The Revised Standard Version, staying much closer to the original, renders Ecclesiastes 11:5: "As you do not know how the spirit comes to the bones in the womb of a woman with child, so you do not know the work of God who makes everything."
This rendering indicates, though not as explicitly as one might wish, that the biblical criterion for a human being — the spirit in man — is present in the fetus. But even if the wording is ultimately deemed too vague to be conclusive, there is one thing which is conclusive: We, as human beings with our finite knowledge, cannot absolutely determine when a fetus (or embryo, or a "glob of cells" — take your pick) has the spirit in man.
And because of the very stringent biblical condemnation of infanticide, we must not take chances. If we indeed do not know whether a fetus has the spirit in man, then we could be committing murder if we practice abortion.
Separate Human Being?
While most scriptural passages indicate that the fetus is a separate human being, there is one passage which might seem to show otherwise, and therefore bears examination.
Translated literally, Exodus 21:22-24 states: "And when men contend and they strike a pregnant woman and her child goes forth, and injury is not, he shall surely be fined as the husband of the woman may put upon him, and he shall give with the judges. [The sense is "according to what the judges determine."] And if injury is, thou shalt give soul for soul, eye for eye, tooth for tooth, hand for hand." (Each word is taken from the Interlinear Hebrew-English Old Testament by George Ricker Berry)
The pro-abortionist argues that since the person who strikes the woman does not pay with his life for the accident, the Bible does not count the fetus as a separate life.
Logically, however, we cannot come to so definitive a statement. Consider the following:
The accident could have taken place at any time during the woman's pregnancy, even as late as the eighth or ninth month. In such a case, it is not at all clear whether the net effect of the whole affair would have been to precipitate a live premature birth, with no harm coming to the baby. In such a case, the offender would simply be paying for the inconvenience caused to the woman and her husband for having altered the natural timetable. The verse does not specify the condition in which "her child goes forth." We therefore cannot necessarily assume that the offending party would even be causing the death of the fetus.
If indeed he did cause the death of the fetus, it would have been accidental, and fall into the legal category of manslaughter. Why then does not the verse say anything about the offender fleeing to the city of refuge (Num. 35:11-15), as was normally the case in manslaughter? The answer is that the flight to the city of refuge was not a punishment for manslaughter, but a humane provision in the Mosaic system to protect the offender from being executed by vengeful relatives and was the custom in the region at the time (and still is to this day among some peoples). We cannot absolutely claim that such an offender might not have availed himself of the city of refuge in such cases as described in Exodus 21:22. Furthermore, the offended husband and wife are recompensed, much the same way as when a person who causes accidental death is sued for a rather large sum of money by the victim's relatives.
Hearts and Minds
At this point pro-abortion arguments become emotional issues concentrating on the often heartbreaking situations where abortion does, on the surface, seem the best way to alleviate clear human suffering. This is where abstract logical analysis meets reflexive human emotion. We see the great potential for suffering for a woman who can't really afford to have the child she is carrying, but we must exercise mental discipline and logical abstract thinking to realize that she might indeed be committing murder by aborting, and that (excluding abortion to save the mother's life) even the possibility of murder is the greater evil.
Murder is murder, and to commit it would be a worse evil than enduring even great amounts of suffering — a fact we recognize when we are talking about children or adults whose very existence causes inconvenience or suffering. There is no other logical choice than to conclude that abortion is wrong.