The Meaningful Chocolate Company said its latest bid for the supermarket giant to sell its products has been unsuccessful.
Founder and director, David Marshall, said: "It seems at Easter they're not very comfortable, for some reason, with stocking Easter eggs for the Christian community.
"They are telling us that they don't think they will sell. This is despite the fact that we have sold over a million Real Easter Eggs."
A number of products made by the company include a 24-page Easter story-activity book which explains the death and resurrection of Jesus Christ.
David Marshall went on to say: "Our Easter eggs are in other supermarkets... and hundreds of shops across the UK.
"I think it's frustrating for Sainbury's customers that when they go into the stores this year, they won't find an Easter egg with a faith message."
Mr Marshall decided to bring out the Real Easter Egg range after he came across an Easter box six years ago which read "Easter is the festival of chocolate and loveliness".
He added: "At Christmas, they [Sainsbury's] are quite happy to provide Advent calendars for pets, believe it or not, but not advent calendars for Christians."
A Sainsbury's spokesperson said: "We review our Easter eggs every year and base our range on customer demand."
Tesco, Morrison and Waitrose are among the retailers to stock the Real Easter Egg.
Listen to David Marshall speaking with Premier's Alex Williams: