Dove with olive branch is a typical image of peace and brotherhood. The concept of dove of peace is closely related to the story of Noah and the great flood. According to the Bible, after other attempts to find dry land, Noah sent a Dove to search for it. The bird came back with an olive branch in its mouth, symbolizing God's promise not to cause such a big natural disaster again. The dove of peace symbolizes unity, love, peace and unswerving commitment to the people you love.
An angel is the messenger of God; he or she is the representative of God, responsible for protecting human beings, protecting God's sheep and executing his will. The same goes for Doves. They are responsible for bringing the message of peace and love, which is a sign of God's blessing to a particular person - when Jesus Christ was baptized, a dove flew down on him from heaven. Angel and dove tattoos are symbols immersed in Christianity; they convey the message that you are a disciple of God and that he has a watch on you. These designs are usually designed to commemorate relatives and let the world know that your lover is now under the protection of the Almighty.
Source: @greybulltattoo