Scripture does not support equating abortion with murder, and the Lord does not direct us to consider a fetus to be the equivalent of a living person. The Hebrew word for life, chayyim, means breathing, and it was given by the Lord for this purpose. A child is born when it takes its first breath.
The punishment for murder was death, life for life, but striking a woman and causing her to lose her fetus was a fine.
“If any should strike any and he should die, to death let him be put to death.”
Regarding abortion, we get the most clarification from the Septuagint.
The Septuagint was a translation of the Hebrew texts into Greek by the 70. It was considered an authoritative translation during the time of Christ and the apostles, and was used by the early church as authoritative Scripture. When quoting the Old Testament, the quotes of the Christ and His apostles,\ match the Septuagint and not the current Masoretic texts, which have been altered over time – as well as the oldest Masoretic texts we have, the Dead Sea scrolls (ref).
The Septuagint clarifies it's a fine when the fetus is not fully formed (μὴ ἐξεικονισμένον), and it is murder if the child comes out fully formed (ἐξεικονισμένον), breathing and alive.
Contemporary Masoretic text Exodus 21:22-25
“If fight men and hurt a pregnant woman to lose child and yet no further harm, surely he shall be punished accordingly as imposed by the husband of the woman and he shall pay as determined by the judge. But if harm follows, then you shall give life for life, eye for eye, tooth for tooth, hand for hand, foot for foot, burn for burn, wound for wound, stripe for stripe.
Septuagint Exodus 21:22-25
ἐὰν δὲ μάχωνται δύο ἄνδρες καὶ πατάξωσιν γυναῖκα ἐν γαστρὶ ἔχουσαν καὶ ἐξέλθῃ τὸ παιδίον αὐτῆς μὴ ἐξεικονισμένον ἐπιζήμιον ζημιωθήσεται καθότι ἂν ἐπιβάλῃ ὁ ἀνὴρ τῆς γυναικός δώσει μετὰ ἀξιώματος ἐὰν δὲ ἐξεικονισμένον ἦν δώσει ψυχὴν ἀντὶ ψυχῆς
If should do combat two men and strike woman in womb having [child] and should come forth her child not fully formed with a fine he shall be penalized in so far as should put upon [him] the husband of the of the woman and he shal give by means of what is fit. However, if fully formed it should be he shall give life for life, eye for eye, tooth for tooth, hand for hand, foot for foot, burn for burn, wound for wound, stripe for stripe.
Brenton's Translation: “And if two men strive and smite a woman with child, and her child be born imperfectly formed, he shall be forced to pay a penalty: as the woman's husband may lay upon him, he shall pay with a valuation. But if it be perfectly formed, he shall give life for life, eye for eye, tooth for tooth, hand for hand, foot for foot, burning for burning, wound for wound, stripe for stripe.”
NETS LXX Translation: “Now if two men fight and strike a pregnant woman and her child comes forth not fully formed, he shall be punished with a fine. According as the husband of the woman might impose, he shall pay with judicial assessment. But if it is fully formed, he shall pay life for life, eye for eye, tooth for tooth, hand for hand, foot for foot, burn for burn, wound for wound, stripe for stripe.”
The Law was so clear Sprinkle noted:
The penalty paid is assessed on the basis of the stage of the development of the dead fetus. The rationale for this view is that the later the stage of pregnancy, the more time has been lost to the woman, the greater the grief for the loss of a child, and the more difficult. This may have been the view of the LXX, which paraphrases אָס֑וֹןיִהְיֶ֖ה וְלֹ֥א as “imperfectly formed child” and translates בִּפְלִלִֽים׃ “with valuation.”
Furthermore, Speiser’s view gains credibility in that penalties for miscarriage actually do vary with the age of the dead fetus in the parallel ancient Hittite Law §17, which states, “If anyone causes a free woman to miscarry—if (it is) the 10th month, he shall give ten shekels of silver, if (it is) the 5th month, he shall give five shekels of silver and pledge his state as security.”
— The Septuagint has the Correct Translation of Exodus 21:22-23, p.7, Thomas F. McDaniel, Ph.D. (2012).
The Lord has not directed us to consider a fetus a living being, nor equate abortion with murder. The Lord is consistent with His Word. If the Lord considered abortion murder, it would've been considered murder here.