"Postul este greu."

Translation: The fasting is hard.

[DewyBukiaPeters]

In English, "post" also translates to "Lent" or "The Great Lent". It's a special name for the fast that takes place before easter (ie. the one that is happening now).

[Lng52-._]

You could also say, "Fasting is hard".

[WarsawWill]

"Lent is hard" should also be accepted, Reported.

https://www.wordreference.com/enro/lent