My transgression is sealed up - The verb rendered sealed up (חתם châtham) means to seal, to close, to shut up; see the notes at Isaiah 8:16; compare the notes at Job 9:7. It was common with the ancients to use a seal where we use a lock. Money was counted and put into a bag, and a seal was attached to it. Hence, a seal might be put to a bag, as a sort of certificate of the amount, and to save the necessity of counting it again.
In a bag - - בצרור bı̂tserôr. So Jerome, “in sacculo.” So the Septuagint, ἐν βαλαντίῳ en balantiō. The word צרור tserôr means usually a “bundle” 1 Samuel 25:29; Song of Solomon 1:13, or anything bound up (compare Job 26:8; Hosea 13:12; Exodus 12:34; Proverbs 26:8; Isaiah 8:16; Genesis 42:35; Song of Solomon 1:13; Proverbs 7:20); but here it is not improperly rendered a bag. The idea is, that they were counted and numbered like money, and then sealed up and carefully put away. God had made an accurate estimate of their number, and he seemed carefully to guard and observe them - as a man does bags of gold - so that none might be lost. His sins seemed to have become a sort of valuable treasure to the Almighty, none of which he allowed now to escape his notice.
And thou sewest up mine iniquity - Noyes renders this, “and thou addest unto mine iniquity.” Good, “thou tiest together mine iniquity.” The word used here טפל ṭâphal means properly to patch; to patch together; to sew to join together as carpenters do their work; and then to devise or forge - as a falsehood; - to join a malicious charge to a person. Thus, in Psalms 119:69, “The proud have “forged a lie” (שׁקר טפלוּ ṭâphalô sheqer) against me,” that is, they have joined a lie to me, or devised this story about me. So in Job 13:4, “Ye are forgers of lies.” The word does not occur elsewhere. The Greeks have a similar expression in the phrase ῥάπτειν ἔπη raptein epē - from where the word ῥαψῳδὸς rapsōdos. The word here, it seems to me, is used in the sense of sewing up money in a bag, as well as sealing it. This is done when there are large sums, to avoid the inconvenience of counting it. The sum is marked on the bag, and a seal affixed to it to authenticate it, and it is thus passed from one to another without the trouble of counting. If a seal is placed on the bag, it will circulate for its assigned value, without being opened for examination. It is usual now in the East for a bag to contain five hundred piastres, and hence, such a sum is called “a purse,” and amounts are calculated by so many “purses;” see Harmer, ii. 285, Chardin, and Pict. Bible in loc. The sense here is, that God had carefully numbered his sins, and marked them, and meant that none of them should escape. He regarded them as very great. They could now be referred to in the gross, without the trouble of casting up the amount again. The sins of a man’s past life are summed up and marked with reference to the future judgment.