ホモテナシ

In China in the Song dynasty (900-1300) the practice of showing 墨跡（ぼくせき）of 禅 masters started.
This practice together with the tea drinking came to Japan in the XIII century, but while 禅 became popular in Japan and *paintings* were often used (for example, in Ashikaga shogunate), the hanging of 墨跡（ぼくせき）didn't catch on until the XVI century.
It was, naturally, 村田珠光（むらた　しゅこう）who introduced the practice of hanging 墨跡 in the tearoom. He was a 禅 student of 一休宗純（いっきゅう　そうじゅん）, who counted the contemplation of scrolls as one of the ways to attain enlightenment; and 村田珠光 tried to develop CNY as a spiritual practice.
So between 1550 and 1650 the trend was initially to hang more paintings than scrolls; but finally reversed! By 1750, it's the rule to hang scrolls.
利休 said in the なんぽろく: no utensil ranks with the hanging scroll in significance and writings done by men in secular life should not be displayed

The following list is compiled from scrolls I have come across personally. Check also Froisland's list.

漢字	reading	season	translation	notes
日日是好日	にちにち or ひび	-	every day is a good day	Ever since that shitty movie I cannot take that scroll seriously anymore
平常心是道	へい　じょう　しん　これ　どう	-	never-changing heart	Ulrich likes this a lot, CJ has one of them
冬嶺孤松秀	とうれい　こしょう　すい	-	on a snowy hill, a lone pine stands out	My Christmas card for 2021
松樹千年翠	しょうじゅ　せんねん　みどり	-	a lone pine, green for a thousand years	got this scroll from rikyucha
閑坐聴松風	かんざしてしょうふをきく	-	rest, sit and listen to the 松風	Hiromi used it for お稽古 in VI 22
無一物	む　いち　もつ	-	not one thing	There's also a 茶碗 with that name
掬水月在手	水を　きくすれば　つきわ　手に　あり	秋	scooping up water, the moon is in my hand	It has a sister scroll, something about flowers
秋空一声雁	しゅうくう　いっせい　の　がん	秋	autumn sky, the sound of a goose
主人公	しゅ　じん　こう	-	master yourself
千里同風	せんり　どうふう	秋	thousand leagues, the same wind	高橋先生
随処作主	ずいしょさくしゅ or ずいしょに　しゅ　と　なる	-	wherever you are, you are the master