Pentecost has changed things forever.
The changes Pentecost caused are seen most clearly in the book of Acts. Here we have the record of the early days of the people of God and their experience with The Holy Spirit. Much has now changed.
First, there was an immediate change (increase) in the number of those who believed the message of Jesus. Luke records that "the Lord added to their number day by day those who were being saved (2:47)." What had begun with about 120 people who had been in Jesus' discipleship band was now in the thousands.
Second, miracles began to occur as seen in chapter 3 and reiterated in chapter 5. The healing of a lame man in chapter 3 is just one of many "signs and wonders were regularly done among the people by the hands of the apostles (Acts 5:12)." This message about Jesus was not only proclaimed with power but was demonstrated in power.
Third, the message that was declared was a combination of declaring Jesus' resurrection and because of this the need to repent. We see in Acts 2, 3, 8, 17, and 26 this recurring message of repent. People are challenged to "change their mind" about Jesus as the resurrected Lord (the meaning of repent). This changing of one's mind is surely the basis of following Jesus as one changes their mind about who is Lord in life.
REFLECT: How much of our experience in life after Pentecost is consistent with these 3 matters? Is it still possible to have these matters in our life and experience? If not, why not?