12 - some examples from the New Testament

1. Twelve years is the length of time the woman subject to bleeding went before being healed by Jesus when she touched him (Matthew 9:20)
2. Twelve is the number of disciples or apostles of Jesus (Matthew 10:1-5, 11:1, etc)
3. Twelve basketfuls of broken pieces that were left over is the number of basketfuls picked up after the feeding of the 5000 (Matthew 14:20, etc)
4. Twelve legions of angels and more is the number of legions Jesus says he could call on to be at his disposal if he wished (Matthew 26:53)
5. Twelve years old is the age of Jairus's daughter who Jesus raised from the dead (Mark 5:42)
6. Twelve years old is the age Jesus was when he and his family firsy went up to the festival, according to the custom (Luke 2:42)
7. Twelve hours is the time of delight Jesus speaks of when a person will not not stumble but see by this world's light (John 11:9)
8. Twelve gates are the number of gates of the New Jerusaem each made of a single pearl with twelve angels at the gatesand on them written the names of the twelve tribes of Israel. (Revelation 21:12, 21)
9. Twelve foundations are under the New Jerusaoelm, and on them are the names of the twelve apostles of the Lamb (Revelation 21:14)`
10. Twelve crops of fruit are the number borne by the tree of life in Paradise, a ctop every month  (Revelation 22:2)

(Also, twelve is the number of the men in Ephesus who were baptised and received the Spirit (Acts 19:17) and twelve stars form a crown that is seen on the head of the woman clothed with the sun, with the moon under her feet in Revelation 12)