Time Domain

Time passes for everything. Nothing is safe from it. The clerics of time are aware of how implacable every moment that passes means in the grand scheme of the cosmos. This understanding give them the privilege to be selected by their deities and be wielders of the gift of time manipulation. Keeping the order of the events as the written fate of the gods is what many stand for. The undeath and immortality of creatures are seen as an unforgivable transgression of this natural force.  The gods of time  -Amaunator, Labelas Enoreth, Cyndor, Chronos and many life domain and death domain deities-  teach the importance of keeping the flow of time, because it is also what maintains the cycle of life in unison with everything that was, is and has to be.

Time magic

The concept of time isn't really present as a category or backed in any game mechanics. Therefore, it is encouraged to both DM and players to describe these spells in a way that fits the flavour. 

For instance, Cure Wounds accelerates a creature's natural regeneration; Feather Fall might make time pass slowly during the fall; Hold Person stops the flow of time for a creature.

These details don't actually change how your spells work but it's a way to make your spellcasting more fun and distinct for the cleric player.

Domain Spells

You gain domain spells at the cleric levels listed in the Time Domain Spells table. See the Divine Domain class feature for how domain spells work. 

Time Domain Spells

Bonus Cantrip

When you choose this domain at 1st level, you gain the mending cantrip if you don't already know it.

Prescience

Also at 1st level, you get glimpses of your immediate future. Whenever you have to make an initiative roll or saving throw, you can impose advantage on the roll.

You can use this feature a number of times equal to your Wisdom modifier (a minimum of once). You regain all expended uses when you finish a long rest.

Channel Divinity: Paradox

Starting at 2nd level, you can use your Channel Divinity to create a safe point in time. As a bonus action, you create an image of yourself where you stand  that lasts until the end of your next turn. This image is only visible to you. Only one image can exist at a time.

As a reaction or when the duration ends, whichever happens first, you reappear to the image position. If you have fired any ammunition or thrown any weapons during the duration, they appear back with you as if you never attacked with them. The image disappears when you return to it or if you fall unconcious.

Deja Vu

At 6th level,  you may travel to a point in time where you didn't opt to some decisions. You regain any spell slots you may have spent through the duration of the Paradox feature (up to 3rd level). 
You also regain any Hit Points lost and restore the conditions you may have suffered during the time Paradox has been active.

Once you use this feature, you can’t use it again until you finish a long rest.

Potent Spellcasting

Starting at 8th level, you add your Wisdom modifier to the damage you deal with any cleric cantrip.

Time Out

 At level 17th, you have learned how the flow of time works on yourself and everything around you:

• Time stop is a domain spell for you.
• For every 10 years that pass, your body ages only 1 year.
• You know how to influence the outcomes of the current timeline. As a reaction, you can force a reroll of any roll that happens the moment you use this feature. You can force the reroll to be made with advantage or disadvantage, and you can choose whether to use the reroll or the original roll. Once you use this feature, you can’t use it again until you finish a long rest.