The number one enemy of the gospel is not the beliefs of the unbelievers, it is actually found in church. Peter when he preached to the Gentiles experienced criticism from inside church.
Acts 11
11 The apostles and the believers throughout Judea heard that the Gentiles also had received the word of God. 2 So when Peter went up to Jerusalem, the circumcised believers criticized him 3 and said, “You went into the house of uncircumcised men and ate with them.”
The Jews couldn’t believe that the gospel was preached to the Gentiles. Why would Peter associate himself with the outcast??? God was breaking their mindset. For the longest time they thought they were the only worthy ones to receive the gospel when in reality nobody is worthy to receive the gospel apart from the grace of God. Peter had to explain why he did such but in the end made a declaration to the believers
17 So if God gave them the same gift he gave us who believed in the Lord Jesus Christ, who was I to think that I could stand in God’s way?” 18 When they heard this, they had no further objections and praised God, saying, “So then, even to Gentiles God has granted repentance that leads to life.”
The gospel is for everyone. Let us not keep it to ourselves. It is not a personal thing.