I must admit I struggle with this from time to time. This reassurance found my inbox this morning so I’m sharing for anyone else who needs it. Feel free to add your own Biblical reminders/encouragement for waiting with confidence.
"In 2 Samuel 5, we see the fulfillment of a long-awaited promise in the life of David. The tribe of Israel became a large nation ruled by David as their king.
David waited roughly fifteen to twenty years to see the fulfillment of this promise. When he was first anointed as king in 1 Samuel 16, though the Bible doesn’t give his exact age, many scholars estimate that David was around ten to fifteen years old. Later, David was anointed as king over Judah, and we are told that he waited another seven and a half years before his final coronation over all of Israel at thirty years of age.
Yes, as we can see in David’s life, good things often do come to those who wait. But we can see in this promise fulfilled that how we wait and what we are waiting for also matter a great deal. During his season of waiting, David had plenty of opportunities to try to gain the kingdom by his own efforts. Instead, David waited for the Lord. Though he had been promised the kingdom nearly two decades earlier, David trusted the Lord to fulfill his promises."