The mitzvah of Beris Milah is introduced with the words, “Ani E-l Shad-ai, his-halech lifanai veheyei tamim — I am E-l Shad-ai, walk yourself before Me, and be whole.”
To me, this pasuk addresses the focus of the most basic open question in Jewish philosophy. Clearly the attention of Yahadus is on keeping mitzvos. But what is the goal of following mitzvos? What is the goal of life, that mitzvos are to help us accomplish?
How are we supposed to read the quote? Is the walking before G-d that is primary, and being whole a side-effect? Or, is being whole the focus of the pasuq, and walking before G-d is a means to reach that temimus?
To the Ramchal (see the opening paragraphs of Mesilas Yesharim), among many others, the goal is coming close to Hashem. In contemporary terminology we would say “deveiqus“, cleaving to G-d. This would be an indication that the primary goal is “his-haleikh lifanai“, walking before G-d.
[Note (2007): I would now categorize the Ramchal differently. He describes a pursuit of temimus, but a tamim person is defined entirely in terms of closeness to G-d. See "Other Tines on the Fork". I would consider his view a synthesis that was perhaps similar to that of Navardok Mussar, but not followed today.]
On the other hand, equally well represented (for example, the opening of the Kuzari) presents man’s quest as “sheleimus ha’adam“, the completion of man. “Veheyei tamim“. Man’s goal is to strive for self-perfection.
On a deeper level, these two approaches are different aspects of the same idea.
A person lives in tension between his spiritual and physical sides — neshamah vs. guf. To achieve wholeness, so that the entire person is working harmoniously, he would necessarily be serving his spiritual goal, and walking in Hashem’s path.
In reverse, if one strives for deveiqus to a singular G-d, how could he be a chaotic battleground of warring urges? Cleaving to G-d forces His priorities to be yours, leaving temimus.
This is not to say that there is no distinction in approach. By stressing different elements, there are profound practical implications. For example, consider the debate between Chassidim and non-Chassidim on the importance of davening in the appointed times. We should be clear that the Chassidic position is that one must invest time to prepare for davening, even if this is at the expense of timeliness — it is not blanket permission to ignore the clock.
Chassidus is a deveiqus-based hashkafah. Therefor, when weighing the relative merits, it is more important to be able to invest time to prepare one’s mind and heart for the act of tephillah, for relating to Hashem, than when the tephillah actually begins.
To someone with a temimus orientation, however, zehirus, meticulousness, care in how each facet of the mitzvah is done, is the more important consideration. Zerizus, haste to do what’s right, is an important middah (personality trait). Both come into play when considering the timeliness of tephillah.
Perhaps this plurality is the whole point of the Torah’s doubled phraseology. Because there are two groups of approaches to the same ends, we don’t want to eliminate one in favor of the other. Each person can pick out a derekh that best suits him — as long as he aims for the proper goal.