Albert Barnes Commentary Psalms 102:18

"This shall be written for the generation to come; And a people which shall be created shall praise Jehovah." — Psalms 102:18 (ASV)

This shall be written for the generation to come - It will be recorded for the instruction and encouragement of future ages. The fact that God has heard the prayer of his people in a time of trial will be so recorded and remembered that it may be referred to in similar circumstances for all time to come, because he is an unchanging God. What he has done now, he will always be willing to do in the future.

And the people which shall be created - Future generations. Each successive generation is in fact a new “creation;” each individual is also; for the essential idea in creation is that of bringing something into existence where there was nothing before. There is a “beginning” of existence in every human being. A human being is not in any proper sense a “development” from a previous being, nor is human life merely a “continuance” of something which existed before.

Shall praise the Lord - They will praise the Lord for what he has now done; they will learn, from the great principles now illustrated regarding his administration, to praise him.