a matter of time

اجتناب ناپذیر
بالاخره اتفاق می افتد
دیر و زود داره ولی سوخت و سوز نداره
an inevitability or eventuality
sth that is or seems sure to happen at some point in the future

It will certainly happen in future

time will tell

Sth will definitely happen but you don't know when

used to say that something will definitely happen in the future
حتمیه
دیر و زود داره ولی سوخت و سوز نداره

صرفا مستلزم زمان است تا

زمان نیازه تا مشخص بشه. . .

The doctor says it's a matter of hours
دکتر میگه تا چند ساعت دیگه مشخص میشه

meaning that an event will take place in the next few hours.