The word “Gospel” (Greek: euaggelion) signifies good news or glad tidings with the emphasis on the adjectives ‘good’ and ‘glad’. Originally the term did not have an exclusive religious significance either in Hebrew or in Greek. However, from the time of Second Isaiah the verb ‘to announce/proclaim good news’ takes on an exclusively religious connotation and it denotes the saving action of God (Cf. Is 40: 9-10; 41: 27; 52: 7-8; 61: 1). In the Greco-Roman world too the words ‘good news’ and ‘to proclaim good news’ were mostly used in a secular and profane sense, referring for example, to victory in war, the birth of a ruler, his accession to the throne, and his decrees. But even in the context of emperor worship, ‘good news’ in the Greco-Roman world assumed a certain religious significances. After the proclamation of the good news of victory of war, the thanksgiving sacrifices offered in the temples were called ‘euaggelia’ (celebration of the good news by offering sacrifices). Similarly, a religious oracle, a solemn announcement of a glad event at some shrine was also called good news.
In the New Testament, the word ‘gospel’ or ‘Good News’ has a special religious significance. It means the good news of salvation, namely, God’s saving action in and through the person of Jesus Christ, his Son. The ‘Good News’ also means in the New Testament, the proclamation of God’s saving actions in Christ.
The term ‘gospel’ means the act of proclaiming the good news as well as the content of that proclamation. It is important to note that both the noun ‘gospel’ and the verb ‘to preach the Gospel/evangelise’ were part of the primitive Christian terminology and that before any of our Gospels were written these terms were well known and frequently used on the Church’s proclamation of the Christian message. However, in the early Church’s usage the term ‘gospel’ never meant a book, or a written work; but simply Good News of Salvation and its proclamation.
Similarly, the early Church could never have used the term in the plural for there was only one Gospel, the Gospel of Jesus Christ. It was only at the beginning of the second century the Gospel was referred to for the first time as a book, a written work (Cf. Didache; 2 Clement 8: 5) but always in the singular until Justin the Martyr, about CE 150, used it in the plural to explain the “memoirs of the apostles” as gospels (Apology 66).