We all fall short of perfection and we all stumble on occasions, But the Grace, Mercy and Love of God sustains us, and He will never leave us nor forsake us.
It is written: Revelation 3:8 I know thy works: behold, I have set before thee an open door, and no man can shut it: for thou hast a little strength, and hast kept my word, and hast not denied my name.
Oh, btw I like your quote which says: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 40:31
God Bless!