For thousands of years, the Devil has been associated with the left hand in various ways and is normally portrayed as being left-handed in pictures and other images.
In the seventeenth century it was thought that the Devil baptised his followers with his left-hand and there are many references in superstitions to the "left-hand side" being associated with evil.
We say "do the right thing" thus favoring the right side to the left one. Jesus is portraited using his right hand and on the contrary, Devil using the left.
What are the traditions of the Church towards left handness?