So the divine instruction against bestiality is still valid. However, its validity isn t based on the old covenant law code, but on the fact that it reflects a proper application of faith and love. We would conclude that bestiality is wrong even if the old covenant said nothing about it. The old provides supporting evidence, but the new provides the authority. When we see that New Testament commands are based on faith and love, we can also discern when it is appropriate to modify New Testament commands and customs.
Modern cultures have different customs for expressing the intent of Paul s command.
These two examples, one discussing an old command that is still valid and the other a new command whose principle should be interpreted culturally, illustrate that we should not view the New Testament as a law book. It gives principles that form the basis of Christian conduct and numerous practical examples of how those principles are applied. The Sabbath foreshadowed our spiritual rest in Christ. If you go back to Genesis 2, where the seventh day is first mentioned, you may notice that it is not described as a 24-hour day with a morning and an evening like the other days. In its spiritual significance, the Sabbath doesn't have an end.