'Three' in the Bible

Then Moses set apart three cities [of refuge] beyond the Jordan toward the rising of the sun (eastward),

“At the end of every third year you shall bring out all the tithe of your produce for that year, and shall store it up within your [city] gates.

“Three times a year all your males shall appear before the Lord your God in the place which He chooses, at the Feast of Unleavened Bread (Passover) and at the Feast of Weeks (Pentecost) and at the Feast of Booths (Tabernacles), and they shall not appear before the Lord empty-handed.

On the evidence of two or three witnesses, he who is to die shall be put to death; he shall not be put to death on the evidence of [only] one witness.

you shall designate three cities for yourself in the central area of the land, which the Lord your God is giving you to possess.

You shall prepare and maintain for yourself the roads [to these cities], and divide the territory of your land into three parts, so that anyone who kills another unintentionally may escape there [for asylum].

Therefore, I command you, saying, ‘You shall set aside three cities [of refuge] for yourself.’

if you keep and carefully observe all these commandments which I am commanding you today, to love the Lord your God, and to walk [that is, to live each and every day] always in His ways—then you shall add three more cities [of refuge] for yourself, besides these three,

“A single witness shall not appear in a trial against a man for any wrong or any sin which he has committed; [only] on the testimony or evidence of two or three witnesses shall a charge be confirmed.