I think there are many types of weary. Most of the time we hear that word we think of the 1st type which I would say is physically tired. If we are weary, our body aches and it is tough to keep moving. But before we get to this type of weary, we run into another type and that is mental weariness. Mental weariness is when we start to believe and then the conversation begins in our head that we cannot go one more step. We're DONE!
It has been proven time after time and you have probably experienced it yourself, right when you think you can't do 1 more sprint, or 1 more push up, or flight of stairs.... your body delivers. You had 1 more physically in you when your mind didn't.
Spiritual weariness goes through the same process. Just when you think the world has you pinned, when you can't take another setback, another failure, another disappointment, another unexplained turn... God's faithfulness and love says yes you can. With Jesus by your side, you can face tomorrow. Get up, hold my hand, and let's move. He is victory, not defeat. When you are feeling weary, just say Jesus and keep moving. He will mount you up on wings like eagles.
"Do you not know? Have you not heard? The Lord is the everlasting God, the Creator of the ends of the earth. He will not grow tired or weary, and his understanding no one can fathom. He gives strength to the weary and increases the power of the weak. Even youths grow tired and weary, and young men stumble and fall; but those who hope in the Lord will renew their strength. They will soar on wings like eagles; they will run and not grow weary, they will walk and not be faint." Isaiah 40:28-31 NIV
"I rejoiced greatly in the Lord that at last you renewed your concern for me. Indeed, you were concerned, but you had no opportunity to show it. I am not saying this because I am in need, for I have learned to be content whatever the circumstances. I know what it is to be in need, and I know what it is to have plenty. I have learned the secret of being content in any and every situation, whether well fed or hungry, whether living in plenty or in want. I can do all this through him who gives me strength." Philippians 4:10-13 NIV