Israel experienced a purgative experience during the time she wandered in the wilderness. Her wandering lasted forty years. Travel through the wilderness would have initially been a short one. The relatively short time that it would have taken them to travel from Sinai to the promised land would have constituted the interval of time in which she would have spent in the desolate desert. However, while on the borders of the promised land she buckled under the weight of her own unbelief. She failed to trust in the promise of the Lord and because she failed to trust the Lord she questioned His goodness and kindness. She questioned His integrity. She questioned His person. This led to the forty years of wandering in the desert in which the Lord would teach Israel to believe.
The wilderness experience was a formative one for the people of Israel. After the forty years had been completed and the people found themselves once again on the borders of the promised land, the purgative function of the wanderings had borne much fruit. The people were ready and able to enter the Land of Promise as the Lord had commanded them. They received the testimony of the Law, as well as the rest of what we know as the Pentateuch just before the entered the land. They were poised to embark on their divinely appointed task to claim the land. Subsequent history will show that the Israelites did not lose sight of this formative experience.
As Palmer Robertson notes in his helpful volume on the wilderness motif, the historical reality of the wilderness served to inform the religious experience of later Israelites. The Psalms are particularly useful in this connection. In remembering the mighty acts of God on her behalf, Israel was able to sing of the glory of the Lord and to life up voices of praise and thanksgiving. He provided Israel with safety and sustenance (Psalm 105). The Psalms also use the wilderness tradition to underline personal guilt (e.g., Psalm 95, 106). Finally, Robertson notes, the Psalms use the wilderness tradition to remind the people of Israel to trust in the Lord and follow His ways (Psalm78). The Israelites saw in the wilderness experience of their ancestors a representation of their own present experience and calling. It was an historical moment that provided them with the means by which to examine their present experiences. This line is picked up in the prophets in which the prophets look forward to both a time of wilderness wandering and renewal. The way the prophets view this wilderness and renewal is fascinating. Isa 41:17-18 reads:
17When the poor and needy seek water,
and there is none,
and their tongue is parched with thirst,
I the LORD will answer them;
I the God of Israel will not forsake them.
18I will open rivers on the bare heights,
and fountains in the midst of the valleys.
I will make the wilderness a pool of water,
and the dry land springs of water.
19I will put in the wilderness the cedar,
the acacia, the myrtle, and the olive.
I will set in the desert the cypress,
the plane and the pine together,
20that they may see and know,
may consider and understand together,
that the hand of the LORD has done this,
the Holy One of Israel has created it.
Verse 18b says "I will make the wilderness a pool of water, and the dry land springs of water." Verses 19-20 continue further in this direction and speak of the fructifying of the wilderness. Anyone who would look upon this will know that it has been by the hand of God. This is a breath-taking statement. It is breath-taking because while it certainly uses imagery tied to the wilderness as a place of want and destitution, it suggests that the wilderness is not something to be traversed, but transformed.
God brought the people of Israel through the wilderness to a land of plenty. The wilderness was but one aspect of the journey, albeit a difficult one. It was a place of destitution and want, a dangerous and harrowing place. However, when God is present, it is a place not to be feared but embraced. One embraces the wilderness experience not as an end in itself, but only ever as a context in which to embrace God more fully and to experience the riches of His divine grace. His presence and promise indicate that the inhospitable place is but a light momentary affliction.
At least one principle difference distinguishes the wilderness wandering of the Exodus generation and the wilderness as a motif in the prophets. The former can be left behind by taking just one more step. The latter, however, can only be left behind by way of a divine act. When the wilderness seems to encompass the whole world, then the wilderness itself must transform into something altogether different. The prophets envision Israel living in a wilderness and while living in such an inhospitable environ they would behold the wilderness sprout into an arboreal paradise. This suggests that the people of God have moved past wandering or traveling to a point of waiting.
The people of God wait for Him to act and do what only He can do: change the world. The time of wilderness will elide into the time of paradise. This is not just a step in the right direction; it is the hopeful expectation of the end for which God created the world. The people of God wait. The wait is an active one, for just as the word of God was to condition every step of the pilgrimage of the Exodus generation, the Gospel of the Lord conditions every aspect of the manner in which we wait. This is the hope about which the prophets prophesied.