Brothers, I do not consider myself yet to have taken hold of it. But one thing I do: Forgetting what is behind and straining toward what is ahead, I press on toward the goal to win the prize for which God has called me heavenward in Christ Jesus. - Philippians 3:13-14
Straining is difficult. Pressing on is hard. Not dwelling on the past is challenging.
Be strong and courageous. Do not be afraid or terrified because of them, for the LORD your God goes with you; he will never leave you nor forsake you. - Deuteronomy 31:6
Good thing we never have to do it alone :)