In God of War Ragnarok, while exploring different worlds, you may ask the question - does the game allow changing the current time to day or night? This page of the guide discusses the topic whether changing the time of the day is available and if so, how changing the time of the day affects the gameplay.
Worlds with the option to change the time of the day
Vanaheim is the only world of the game in which the time of the day changes - from day to night and night to day.
The first change of the time is a scripted event - it takes place during The Reckoning story quest.
Using the Celestial Altar
You receive an option to manually change the time of the day during the course of Creatures of Prophecy story quest.
To change the time of the day, visit any Celestial Altar - all newly found altars are added to Vanaheim map, and we show an exemplary one in the screenshot. You can return to them at any time and the change costs nothing.
Changing the current time isn't only an aesthetic choice. Some locations and passages may be blocked at certain times of the day. For example, you may come across a barricade similar to the one in the picture above, and this type of them is indestructible.
To overcome the obstacle, you need to return to the nearest Celestial Altar, change the time of the day and return to the area where the barricade was. The passage should already be unlocked.
Additional note - In the game, you will not experience a continuous passage of time and the change of time of day never occurs on its own. You have to force all changes yourself.