"What is often lacking in the world in terms of unity could be seen as lacking in the church as well," said Teddy Oprenov, General Secretary of the Baptist Union of Bulgaria.
Preaching from Ephesians 4, Mr Oprenov reminded Baptists of their acceptance into one body by one baptism, one Lord and one Holy Spirit.
"You cannot separate and divide the church into parts and pieces without dividing who God is. God is not to be divided. He is one," he said.
Mr Oprenov urged Baptists not to allow their different gifts to become a source of division.
"The gifts are opportunities to do ministry but very often our gifts clash," he said. "How often do we take sides based on the gifts given to us when they are there to unite us, not to separate us, not to enable us to lift ourselves up or look at others from above."
He also encouraged Baptists to be mindful of their own quality of character and "inner conduct".
"Unity is a personal matter. It is not a matter of relationships only," he said.
"Relationships follow what we have in our hearts. We worship because we want to prepare our hearts for whatever comes.
"Do we prepare our hearts in the right way for unity? If there is a wall in the heart there cannot be peace between people."
Mr Oprenov urged Baptists to remember the unity embodied in the Lord's Supper and Paul's exhortation to make every effort to keep the unity of the Spirit.
He said: "The Lord's Supper is a sign of unity because Christ's body was smashed, broken, His blood was shed.
"Try to separate the grapes in the wine, try to separate the grains in the bread. It's not possible.
"Let us remind ourselves of our calling to unite … for the sake of the Kingdom of God, for the sake of the Baptist Union, for the sake of the new generation that will guide the history of the next 400 years."