The creator of the universe works in mysterious ways. But he uses a base ten counting system and likes round numbers. Scott Adams
Symbolic of Difference or Division
Genesis tells the account of God creating the heaven and the earth, of God dividing the light from the darkness, and of God separating the water of heaven from that of the earth. We see the division and the duality the number two denotes.
Symbolic of Important Assignment
Two angels destroyed Sodom in Genesis 19:1. Two spies gathered military intelligence in Jericho in Joshua 2:1. Two by two, Jesus sent out his disciples he empowered to drive out unclean spirits in Mark 6:7.
Symbolic of Minimum Witnesses
The worldview of Deuteronomy 19:15 states that two is the minimum number of witnesses (for establishing a case in the justice system).
For where two or three are gathered together in my name, there am I in the midst of them. Matthew 18:20.
Matthew 18:20 is a reminder of Deuteronomy 19:15 that two is the minimum number of people God expects a dispute to be witnessed by.
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Luke 24:13-35 records a story of two travelers walking on the Emmaus Road. It was on the third day of the death of Jesus. The two travelers were joined by Jesus on the road but they didn't recognise him... until the breaking of bread by Jesus.