Picture in English comes from the Latin pingere meaning ‘to paint’, via the Latin pictus, past particple form of pingere. This comes to English via French.
Pingere descends from the PIE *peyḱ- meaning colour, which is also the source of the Sanskrit पिंशति (piṃśati) and the Greek πῐκρός (pikrós), meaning ‘to carve’ and ‘pointed’ respectively. Other descendant words include Greek ποικίλος (poikílos, ‘coloured’), Sanskrit पिशङ्ग (piśáṅga, ‘reddish’) and Lithuanian piẽšti ‘to draw’ among many others.
With picture we in English get words such as depict, with the de- prefix here meaning completely, and deriving from the Latin depingere, which can be translated as ‘portray’, but also paint or colour. Depingere occurs for instance in Apuleius’ Metamorphoses, at Book 6 chapter 29 in the form depictam.
A picture paints a thousands words, and dates to certainly 1927, and the Printer’s Ink magazine on December 8th, where that phrase appears as an ancient Chinese proverb. Some say the phrase originates from American Fred R. Barnard writing in that publication. Printers Ink also has the phrase appear in 1921 and 1927. Other examples include a newspaper quoting then editor Tess Flanders in 1911, and the Syracuse Advertising Club member Arthur Brisbane wrote in that same year ‘use a picture it’s worth a thousand words’. One instance of the phrase comes from a 1918 paper, and an advertisement for the San-Antonio Light newspaper.
Charlotte Brontë precedes them all, writing in Jane Eyre (1847) ‘the letter press I cared little for, each picture told a story’.