Job 1:5
And it was so, when the days of their feasting were gone about, that Job sent and sanctified them, and rose up early in the morning, and offered burnt offerings according to the number of them all: for Job said, It may be that my sons have sinned, and cursed God in their hearts. Thus did Job continually.
In the earliest order the head of each family served as both ruler and priest of his own household, so Job himself offered the sacrifices for his family, and only later, as the race multiplied upon the earth, did divinely appointed men perform this solemn worship of sacrifice for the people. When the cycle of his children's feasting was gone about, he sent and sanctified them and rose up early in the morning to offer a burnt offering according to the number of them all, because he said it might be that his sons had sinned and cursed God in their hearts, and thus he did continually. His giving to God was made before the Mosaic system was established, showing that giving to God for religious purposes is a longstanding principle.
His sacrifice meant that the blood of beasts was to be associated with the blood of the Son of God, and the death of the victim evidenced that the penalty of sin is death. By the act of sacrifice he acknowledged guilt and manifested faith looking forward to the great and perfect sacrifice of the Son of God which the offering of beasts prefigured. Without the atonement of the Son of God there could be no communication of blessing or salvation from God to humanity, because God upholds the honor of His law and transgression of that law caused a fearful separation between God and humanity. Where Adam in innocence enjoyed direct, free and happy communion with his Maker, fallen humanity communicates with God through Christ and angels.
The verse establishes the duty of the head of a household to acknowledge God morning and evening and to confess both personal sins and the sins of the children, regardless of difficulties. It presents Job as one of God's appointed witnesses who exposed himself to reproach and persecution for the truth's sake. He was deprived of his worldly possessions and so afflicted in body that he was abhorred by his relatives and friends, yet he maintained his integrity. His experience gives strength and comfort to others by proving that God causes the schemes of wicked men to work for good to those who in trial and conflict maintain faith and loyalty. It bears witness to the faithfulness of God's promises, His abiding presence and sustaining grace, and the power of faith to withstand the powers of the world and to rest in God in the darkest hour.