It is commonly understood that a chok (often translated as a “statute”) is a commandment in the Torah without an underlying rationale, the quintessential chok being that of the red heifer in this week’s parashah. This is indeed how Rashi seemingly understood the definition of a chok (see his commentary to Exodus 15:26).
Nahmanides (Vayikra 19:19) and Maimonides strongly disagreed with this interpretation of chok. In their eyes, it would be theologically preposterous for the Divine to issue a commandment that lacks a rationale. All commandments, including the statutes, must have reasons; a chok is merely a commandment whose rationale is not readily appreciated owing to the weakness of our intellect or the deficiency of our knowledge (Guide for Perplexed 3:26).
Thus, while the laws of kashrut or the prohibition against wearing a garment of wool and linen or the red heifer of this parashah are classified by the sages as a chok, this does not mean they lack logic; rather, more intellectual effort is needed by humans to be able to uncover the depth of the commandment’s rationale.
Elsewhere, Rambam explains the psychology of those that seek to understand a chok as something not comprehensible: if commandments are too easily understood by the human mind and their benefit to humanity clearly evident, “it would be as though they originated in the thought and reason of some intelligent being” (Guide 3:31).
On this view, the more irrational a commandment, the more attributable it is to the Divine. Rambam opposed this view and states that the exact opposite is true: the purpose of Torah is for human benefit and improvement and there must be inherent wisdom and moral benefit in each and every commandment in Torah.
Rambam points to a famous verse (Devarim 4:5-6) where Moses tells the Israelites that the nations of the world will look in admiration at the chukkim, statutes, of the Torah and remark what a wise nation the Israelites are (Guide for Perplexed 3:26).
What this means is that while on the one hand we must “blindly” accept each and every one of God’s chukkim even though we may not understand them, at the same time we are encouraged to make every intellectual effort to attempt to comprehend their reason. In Judaism, our faith in God can only be enhanced by our constant quest for reason and truth.