Theologians sometimes refer to the new covenant as the age of the Spirit, and rightly so, for the Holy Spirit has been poured out abundantly on the people of God in this administration of the Lord’s covenant of grace (Acts 2:1–41). That we live in the age of the Spirit, however, does not mean that the third person of the Trinity did not work among the people of God under the old covenant. Indeed, He was active, though not in precisely the same way as He is today.
Clearly, the Holy Spirit has always been the agent who regenerates people. Jesus expected Nicodemus to understand this truth, as he was a teacher of old covenant Israel (John 3:1–15). God’s Spirit gave old covenant believers the faith they needed to trust in His promises, just as He gives new covenant believers faith today to entrust themselves to the fulfillment of these promises in Christ Jesus (Eph. 2:8).
At the same time, even though all old covenant believers experienced the Spirit’s work of regeneration, it also appears that not all old covenant believers enjoyed the same kind of gifting and power evident in the new covenant. In today’s passage, for example, Joshua is said to be a man “in whom is the Spirit” (Num. 27:18). This designation is given to a select few in the Old Testament, usually the leaders of Israel (see, for example, Gen. 41:38; 1 Sam. 16:13). But now, on the other hand, even believers without a leadership role in the church have the Spirit in His fullness (Rom. 5:5). Messiah Jesus baptizes all of His people “with the Holy Spirit and fire” (Matt. 3:11).
It is difficult to describe precisely how our richer experience of the Spirit today compares to how old covenant believers enjoyed Him, especially since we all get discouraged and sometimes feel as if the Holy Spirit is far from us. Still, there is plenty of evidence that shows the Spirit is working more powerfully in the present age than He did during the old covenant. Perhaps the greatest proof for this is the ingathering of the Gentile nations. For all the problems the church has faced throughout the ages and even now endures, it is indeed serving as a light to the nations in a way that old covenant Israel never did. By the drawing of the Spirit through the witness of the church, even the non-Israelite nations are coming to faith in the God of Israel (Acts 15:1–11).