Hallow (verb; noun), to make holy, to sanctify; a holy person, a saint.
From old English haliga, halga — Middle English halwe, related to hælþ (being whole) — the origin of the modern English “health”.
Obsolete word except in two important instances: Halloween (All-Hallows-eve), and in the Lord’s Prayer:
9 After this manner therefore pray ye: Our Father which art in heaven, Hallowed be thy name.
10 Thy kingdom come, Thy will be done in earth, as it is in heaven.
11 Give us this day our daily bread.
12 And forgive us our debts, as we forgive our debtors.
13 And lead us not into temptation, but deliver us from evil: For thine is the kingdom, and the power, and the glory, for ever. Amen.
Matthew 6:9-13