The commandment to love your neighbor as yourself is directly followed by the words "I am God." What is the reason for this juxtaposition? One explanation given by Chazal is that God is telling us, "the way in which you treat other people is the way that I, God, will treat you." This goes for both the micro and the macro. In the micro realm, if we are knit-picky over what our neighbors do privately, God will be more judgmental of what we do in our personal lives as well. In the macro realm, if we do not publicly treat each other with dignity and respect, God will bring about circumstances in which we, as Jews, are not treated well in public either. Unfortunately, history has proven this time and again.
In addition to the "I am God" phrase mentioned above, there are three consecutive verses at the beginning of the same chapter which end with the words "I am Hashem your God." Rabbi Chaim of Volozhin elucidates a very meaningful interpretation of these verses. He states that the reason for the apparent phrase redundancy is a reflection of the three different categories commonly found among the Jewish people:
The first category addressed by the Torah are God-fearing people who meticulously observe every commandment, no matter how big or small. These Jews are regarded as holy and are told by the Torah to continue to live their saintly lives and attain even more closeness to God. The verse ends with "I am Hashem your God" - i.e. of the righteous Jew.
The second category includes Jews who properly observe the major commandments, such as honoring one's parents and observing the Sabbath. The Torah tells these Jews that although everyone should keep these commandments, you will be enveloped by the Divine Presence as a reward. The verse ends with "I am Hashem your God" - i.e. of the average Jew.
The third category addresses Jews whose attachment to Judaism is tenuous. The Torah beckons this group of people not to worship false gods. Although you may have abandoned ritual observance, do not renounce the faith of your fathers and you will remain a part of the Chosen People. The verse ends with "I am Hashem your God" - i.e. of the borderline Jew.
Rabbi Chaim provides us with a tremendous lesson. No matter how religious, middle-of-the-road, or secular we may be at a given time in our lives, God treats every single one of us with love and respect. Since we are taught to emulate the characteristics of God, the message is obvious. Just as God regards all of us as a part of the same inseparable unit, we must also train ourselves to recognize the importance of fellow Jews. Even if we are troubled by one's level of observance - whether they are "too religious" or "too secular" for us - nevertheless, treat them as decently as possible.