Thank you for the question, “Who first received the gospel?”
As one reads the Gospels and Acts, there are two persons who may be considered the first to receive the Gospel:
A. It can be Zechariah, the father of John.
The angel gave Zechariah the message of the Good News. In Luke 1, it says this, “6 He will bring back many of the people of Israel to the Lord their God. 17 And he will go on before the Lord, in the spirit and power of Elijah, to turn the hearts of the parents to their children and the disobedient to the wisdom of the righteous—to make ready a people prepared for the Lord.” (NIV).
Zechariah was doubtful of what he saw and heard from the angel. He was among the first to be given the message of the coming Lord to make a people ready for the Lord.
B. It can be Simeon, the priest.
The Spirit told Simeon that he will see the Lord’s anointed before he passes away. Luke 2 says this, “25 Now there was a man in Jerusalem called Simeon, who was righteous and devout. He was waiting for the consolation of Israel, and the Holy Spirit was on him. 26 It had been revealed to him by the Holy Spirit that he would not die before he had seen the Lord’s Messiah. 27 Moved by the Spirit, he went into the temple courts. When the parents brought in the child Jesus to do for him what the custom of the Law required, 28 Simeon took him in his arms and praised God, saying: 29 “Sovereign Lord, as you have promised, you may now dismiss[d] your servant in peace. 30 For my eyes have seen your salvation, 31 which you have prepared in the sight of all nations: 32 a light for revelation to the Gentiles, and the glory of your people Israel.”
Simeon received a special revelation that he will see the one who will bring salvation to all the nations. The timeline is unclear whether Simeon received this revelation before Zechariah or did Simeon received his revelations after Zechariah received his revelation.
SUMMARY: I am incline to think that Simeon received the first Gospel of the coming Savior-Messiah to Israel.