Bible Answer

Did the ministry of the Holy Spirit change in the NT?

You recently taught that the Holy Spirit was not given to men until Pentecost, but I know of several earlier times in scripture where the Holy Spirit was given to specific individuals (e.g., John the Baptist, Mary, etc.). Is there some different meaning or essence to the Holy Spirit’s ministry prior to Pentecost, as compared to after? 
 

First, the Holy Spirit has always been required to bring a person to saving faith, whether before or after Christ's day. It was this way for the believing in Israel:

Is. 44:2  Thus says the LORD who made you
And formed you from the womb, who will help you,
‘Do not fear, O Jacob My servant;
And you Jeshurun whom I have chosen.
Is. 44:3 'For I will pour out water on the thirsty land 
And streams on the dry ground;
I will pour out My Spirit on your offspring
And My blessing on your descendants;
Is. 44:4 And they will spring up among the grass 
Like poplars by streams of water.’
Is. 44:5  “This one will say, ‘I am the LORD’S’; 
And that one will call on the name of Jacob; 
 And another will write on his hand, ‘Belonging to the LORD,’ 

Notice the Lord promises to pour out His Spirit on future generations of Israel to bring them to the Lord in faith. This has always been the ministry of the Holy Spirit. In the times of Christ, we're told this:

Matt. 22:43 He  said to them, “Then how does David in the Spirit call Him ‘Lord,’ saying,
Matt. 22:44      ‘THE LORD SAID TO MY LORD,
“SIT AT MY RIGHT HAND,
UNTIL I PUT YOUR ENEMIES BENEATH YOUR FEET”’?

Jesus credits the Spirit with revealing the truth of Messiah to David. Once again, we see that the Spirit of God is responsible for a saving knowledge of God.

Likewise, in the age of the church, the Spirit must draw men and women to Jesus in order to be saved, but there are differences in the Holy Spirit’s ministry to men and the manner of His operation after Pentecost.

Prior to Pentecost the Holy Spirit is shown in scripture to come “to” men or to come “upon” men. For example, Saul experienced the Spirit of the Lord coming upon him just before he entered into battle (1Sam 10:6). Later after Saul had disobeyed God and disqualified himself to hold the throne of Israel, the Spirit departed from Saul (1Sam 16:14). This pattern is repeated in other places in the Old Testament. The Spirit of the Lord will come upon men for a period of time, and at some later point the Spirit will depart when His purpose has been met.

After Pentecost, the Holy Spirit’s ministry to men changed for the believer. In this age the Holy Spirit is charged with selecting a Bride for Christ and protecting Her until the Groom arrives at the rapture to claim Her. [This process is pictured in the story of Isaac and Rebecca, where Isaac pictures Christ, Rebecca pictures the Church, Abraham pictures the Father, and Abraham’s unnamed servant pictures the Holy Spirit (see Gen 24).]

Today the Holy Spirit unites with the spirit of each believer as a seal and down payment of the believer’s future inheritance (see 2Cor 1:21-22). So once the Spirit indwells a believer, the association is permanent.

Secondly, the Holy Spirit’s manner of operation changed after Pentecost. Prior to Pentecost, the Spirit would empower (i.e., anoint) men to perform a certain mission or task as commanded by God. Today the Holy Spirit works to change the heart of the believer, to convict of sin and purify by the sword, the word of God.

Finally, the post-Pentecost ministry of the Spirit includes fulfillment of Jesus’ promise to send the Helper or Teacher, the One Who will bring to mind Jesus’ teachings (John 14:26). This is a unique New Testament role for the Holy Spirit: to explain Jesus’ teachings. These N.T. roles give the Holy Spirit a unique operation and purpose during the Church age.