This is a number which is but little used. It may be connected with 3, but there appears to be little definiteness in it.
Acts 3:1 speaks of the 9th hour as the hour of prayer. Gal. 5:22-23 shows the fruit of the Spirit in a nine fold way. Deut. 3:11 gives 9 cubits for the length of Og's iron bedstead. In Judg. 4:3, Jabin's chariots of iron were 900.