NOTES for Psa 71
Whoever trusts in the Lord is certain of His support and does not doubt that in any situation he will find a Protector in Him. The psalmist hopes to remain united with Him in the future as well and asks the Lord not to abandon him in old age. Such a desire is understandable, but here we may ask a question, not so much of the psalmist as of ourselves: the Lord remains faithful to His promises, but are we always faithful to Him? Do we have the right to claim that we will not turn away in old age from the paths to which He has called us? And if not, do we have the moral right to demand His constant protection?
It seems that we should not fall into excessive apprehensiveness; it is akin to excessive self-confidence, for extremes meet. Aware of our weaknesses and falls, we should not abandon hope in God. He sees our weaknesses better than we do, and He is the only One who can keep us from falling. That is why the question of a “moral right” does not arise: not only may we turn to Him for support, we must do so if we want to remain faithful to Him.