Serving wears you down. The church that asks, the children who ask, the work that asks, sometimes the same day. There are seasons when you feel emptied before you have even begun, and the temptation is strong either to cut everything off, or, on the contrary, to grit your teeth until exhaustion. Isaiah does not promise you that fatigue will disappear; he says something else.
The strength of God’s servants is not a personal reserve we nibble at until it gives out — it is a strength that is renewed in the One we lean on. You do not have to hold on with what is left. You have to wait — in the biblical sense, to actively hope — and you start again.
“But they who wait for the LORD shall renew their strength; they shall mount up with wings like eagles; they shall run and not be weary; they shall walk and not faint.”
Isaiah 40:31