Waiting upon the Lord does not mean sitting around doing nothing and waiting for the Lord to suddenly appear in the clouds or to perform some great miracle.
Waiting upon the Lord means to wait on the Lord like a waiter serves a guest at a table; taking the guest's order and filling the order with dignity and patience.
Brethren, we must serve the Lord with patience and longsuffering all the days of our lives without grumbling nor complaining, but with thankful heart filled to overflowing with zeal born of the hope of His coming.
This is what is meant by the scripture, But they that wait upon the
Lord shall renew their strength; they shall mount up with wings as
eagles; they shall run, and not be weary; and walk and not
faint.