Again his brothers didn't mind David following them to battle in I Samuel 17... Notice what takes place in this chapter.
1. David's Work was Unnoticed... in the first 11 verses of chapter 17 David isn't mentioned. Our work and service sometimes goes unnoticed and we tend to feel our service doesn't matter to anyone. Don't be hoodwinked by the devil's tactics. Your service is very important.
2. David's Help was Unwanted... when david showed up with the bread and cheese Goliath appeared and began to blaspheme David's God. David took offense and ask the question "who is this uncircumcised Philistine"? When David initiated action his eldest brother turns on him and even Saul tells him he wasn't ABLE to face Goliath. The word "ABLE" used by the Holy Spirit in verse 33 means to prevail, overcome, endure, or accomplish. Saul wasn't much of a cheerleader. He is telling David he can't overcome or prevail over his giant. Thank God he didn't give up because his help wasn't wanted. Many of you may feel the same way but be encouraged your help is needed.
3. David's Heart was Unwavering... with all the disappointments and discouragements David wasn't deterred in his quest to please God. He was strengthened by past victories where one would see as inevitable defeat. Don't allow the giant in your life to hinder you. Don't allow disappointments from friends or family to discourage you. Remember God had already chosen and anointed David and God was placing David in a training session that he might be well equipped for future engagements.