'Three' in the Bible

Then Moses had three towns marked out on the far side of Jordan looking to the east;

At the end of every three years take a tenth part of all your increase for that year, and put it in store inside your walls:

Three times in the year let all your males come before the Lord your God in the place named by him; at the feast of unleavened bread, the feast of weeks, and the feast of tents: and they are not to come before the Lord with nothing in their hands;

On the word of two or three witnesses, a man may be given the punishment of death; but he is not to be put to death on the word of one witness.

You are to have three towns marked out in the land which the Lord your God is giving you for your heritage.

You are to make ready a way, and see that the land which the Lord your God is giving you for your heritage, is marked out into three parts, to which any taker of life may go in flight.

And so I am ordering you to see that three towns are marked out for this purpose.

If you keep and do all these orders which I give you today, loving the Lord your God and walking ever in his ways; then let three more towns, in addition to these three, be marked out for you:

One witness may not make a statement against a man in relation to any sin or wrongdoing which he has done: on the word of two or three witnesses a question is to be judged.