Those two words

I am 69 years old, I often have said throughout life that when we are young we see this very long time in front of us, and a very short period in back of us. In midlife we see equal times , a length of time gone by and what we think is how long our time on earth will be in front of us.
I now see a very long time behind me, (life gone by) and a big question mark in front of me. None of us know the time we have on this earth. I also see my mind getting better and my body not cooperating with my mind. I think I can do something but the body says, "wait a minute, I have something to say about that now, you have to take me into consideration. " I used to be able to abuse my body and it would cooperate, no more. I am not complaining, I am in good health and my body treats me well in almost every situation.
The greatest mysteries we have are how long we will be here and what condition will we be in as the years pass.
I often pray about this and ask for healing and health and happiness, I keep getting those two words back from God, "Trust Me."