The angel Gabriel, who visited Mary, is God's chief messenger angel and only appears to very important people in the Bible. The first words that Gabriel spoke to Mary 'Greetings, you who are highly favoured! The Lord is with you.' are very important words. 'Highly favoured' means 'God's holy grace is upon you' and is a divine blessing from God - something that would have never normally been said to a peasant girl like Mary! She would have been very scared by this and that is why Gabriel said 'Do not be afraid'.