I have always heard teachers and preachers alike say, if you see one thing stated more than once in the same passage. That is something to really pay attention to, to watch out for and take notice. Verse 14 Samuel makes a plea to the people to 'fear the Lord and serve Him' and then again in verse 24 he says 'fear the Lord and serve Him in truth with all your heart.' These statements come with either a blessing for following the command or a curse for not following the command.
This is the heart of what Samuel is saying. He told Israel that he will do his part and pray to the Lord for them, but he implored to them that they do their part. It's easy for us to miss doing our part when we don't seem to have a deadline or unless it comes with some sort of payday. We easily forget about what we should be doing, the things that the Lord would have us do. Following His commands, and following in Jesus footsteps. Let us remind each other to do good and to bless the Lord by being His true children. Speaking His words, doing His works, serving like Jesus serves, loving the way Jesus loved. Brother and sister, let us try to make a commitment to help each other to serve better and love our Father by seeking Him and doing His will.