Have mercy upon me, O Lord, for I am in trouble,.... A sudden change of case and frame this! and so it is with the people of God; as soon as, out of one trouble, they are in another; these are what are appointed for them, and lie in their pathway to heaven, and are necessary; and under them it is quite right to betake themselves to the Lord, who is a merciful God; and it is best to cast themselves upon his mercy, having no merit of their own to plead with him; and they may freely tell him all their distresses, as the psalmist here does, and hope for grace and mercy to help them in time of need; mine eye, is consumed with grief; expressed by tears; through the multitude of which, by reason of trouble, his sight was greatly harmed; according to Jarchi, the word signifies, that his sight was so dim as is a man's when he puts a glass before his eyes, to see what is beyond the glass: this shows that the invention of spectacles was before the year 1105; for in that year Jarchi died; and proves it more early than any other writer has pretended to (a); for the commonly received opinion is, that they were invented at the latter end of the thirteenth or beginning of the fourteenth century; but the apostle, as A-Lapide thinks, respects them, in Co1 13:12; and they are mentioned by Plautus (b), who lived almost two hundred years before the birth of Christ: the same Jarchi observes on Psa 6:7; yea, my soul and my belly; perhaps he could not eat his food, or digest it, which brought upon him internal disorders, and even brought his soul or life into danger. (a) See Chambers's Dictionary on the word "Spectacles". (b) Vid. Ainsworth's Lat. Dict. in voce "Conspicill". & Panciroll. Rer. Memorab. par. 2. tit. 15. & Salmath. in ib. p. 268.