Whoever says "I know him" but does not keep his commandments is a liar, and the truth is not in him, but whoever keeps his word, in him truly the love of God is perfected. By this we may know that we are in him: whoever says he abides in him ought to walk in the same way in which he walked. (1 John 2:4-6)In the circles I used to run in more heavily, teachings like the Sermon on the Mount were often more or less dismissed as "law", and therefore not really applicable to questions of Christian ethics. This has led to a lot of Reformed types creating confusing notions of "vocation", "just war" and a confused two-kingdoms notion. It also meant that often ethical and practical teaching tended to be drawn equally from the Old Testament and the New. But is that what was intended from the teachings of Christ? Was He just telling us what we couldn't do so that we would rely on Him? Certainly that is an aspect, an important one. It also seems that the consistent admonition to demonstrate our love for Him by keeping His commandments would indicate that He expected us to follow after Him by keeping those commandments that He gave us, both the general teaching like the two-fold Great Commandment and in more specific teachings like the Sermon on the Mount, His parables and specific teachings on topics like wealth.
When I read something like this, it strikes me that most of what we are told shows that we are "Christians" like going to church, "tithing" and being a supporter of traditional marriage don't really show up on Christ's radar but the things He did teach about like loving our enemies, being meek peacemakers and eschewing wealth are either ignored or explained away. It makes one think that we are spending a lot of time and money and effort on stuff that Jesus didn't care all that much about and not a lot of focus on what He did care about.
If following His commandments is as important as John says above, ought we not invest a lot more of our effort in equipping others to walk as He walked?