The Literal Commandment
"If the place which the LORD your God chooses to put His name is too far from you, then you may slaughter of your herd and flock which the LORD has given you, as I have commanded you; and you may eat within your gates whatever you desire." (Deuteronomy 12:21)
This commandment permits us to "slaughter of your herd and flock" on one condition: "if the place which the LORD your G-d chooses to put His name [i.e. the Temple in Jerusalem] is too far from you. If that condition is not true then the place where animals should be slaughtered is the Temple and the normal process of ritually slaughtering the animal would be followed. The permission given in this commandment is only on the location... not the process.
Messiah Says
Messiah implicitly affirmed this commandment when He spoke about the Law:
"Do not think that I came to abolish the Law or the Prophets; I did not come to abolish but to fulfill. For truly I say to you, until heaven and earth pass away, not the smallest letter or stroke shall pass from the Law until all is accomplished. Whoever then annuls one of the least of these commandments, and teaches others to do the same, shall be called least in the kingdom of heaven; but whoever keeps and teaches them, he shall be called great in the kingdom of heaven. (Matthew 5:17-19)
Pictures of Messiah
Messiah had to die in the specific manner prophesied about Him. His hands and feet were pierced (Psalm 22:16, John 19:23, 34, 37). As our Passover Lamb, none of His bones were broken (Exodus 12:46, Psalm 34:20, John 19:36). Just as He was slaughtered in a specific manner on our behalf to sustain us spiritually, so our food is to be slaughtered in a specific manner to sustain us physically. This specific form of slaughter can serve to remind us of Him.
How Messiah Fulfilled
We know that Messiah did not sin (Hebrews 4:15) and so we know Messiah fulfilled this commandment by either (a) ritually slaughtering an animal before eating it or (b) someone else ritually slaughtered the meat He ate.
Traditional Observance
The traditional observance of this commandment is found in its literal meaning: ritually slaughtering an animal before eating it.
Shechita is the Jewish religious and humane method of slaughtering permitted animals and poultry for food. It is the only method of producing kosher meat and poultry allowed by Jewish law.1 The process of kosher slaughter is described at Shechita UK.
Other Notes
We are able to fulfill this commandment today and should ritually slaughter an animal before eating it. If you don't slaughter your own animals then buying meat that is ritually slaughtered is the way to fulfill this commandment.
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