In the actual performance of the work of service, however, it is fitting to rely on Him after one has chosen it wholeheartedly and sincerely resolved and endeavored to do it with a pure heart and intended it for the sake of His great Name. Here it is our duty to implore Him to help us and guide us. Through Tehilim, the psalmist have already chosen the service for GD but prayed for two things.
1. That He unify his heart and strengthen his choice in His service by removing worldly distractions from his heart and sight
2. That He strengthen his limbs for the performance of the acts of service pg431/433