Deuteronomy 30:11

For this commandment which I command you today is not hidden from you, nor afar off.

wondrous either mysterious or a superhuman task, which you will be unable to perform

FOR THIS COMMANDMENT. The meaning thereof is that it refers to the entire Torah. But the correct interpretation is that when he refers to the entire Torah, he says [as above] Every commandment which I command thee this day. Rather [the expression used here] this commandment refers to [the commandment of] repentance aforementioned, for the verses, and thou shalt bethink thyself; and thou shalt return unto the Eternal thy G-d, Verse 2. constitute a commandment, wherein he commands us to do so. It is stated in a future tense [rather than in the imperative] to suggest, in the form of a pledge, that it is destined [that Israel will repent]. And the sense thereof is to state that if thy outcasts be in the uttermost parts of heaven and you are under the power of the nations, you can yet return to G-d and do according to all that I command thee this day,, Verse 2. for the thing is not hard, nor far off from you, but rather very nigh unto thee to do it at all times and in all places. This is the sense of the expression, in thy mouth, and in thy heart, that thou mayest do it meaning that they confess their iniquity, and the iniquity of their fathers by word of their mouth, and return in their heart to G-d and accept the Torah upon themselves this day to perform it throughout the generations, as he mentioned, thou and thy children with all thy heart, as I have explained., and in Verse 6.

כי המצוה הזאת, and the reason that I said in verse 1 that the repentance must be wholehearted and among the nations, i.e. while you are still in exile, is so that it can trigger your salvation. For, indeed this commandment, i.e. the one to return to G’d in sincere penitence אשר אנכי מצוך היום, Moses reminds the people that in the list of sacrifices in Leviticus 5,5 et al, where various kinds of sin and guilt offerings are listed as means to expiate for the error committed, the essential refrain is always “והתוודה אשר חטא,” that the guilty person first confesses his mistake, his sin, even the one committed inadvertently. Compare also Numbers 5,6-7)

לא נפלאת היא ממך, so that you would need to ask the prophets in order to understand it correctly.

ולא רחוקה היא, so that you have to ask the leading Torah scholars of your generation who live a long way from you to explain how to observe this commandment. You can easily observe this commandment even in the Diaspora where you may not have any Torah scholars nearby.