It varied a bit. I presume you're talking about the time Lincoln served a single term in the House as a Whig from 1847-49. In the case of Lincoln's IL colleagues at the time, he served about the shortest. Only his seatmate in the adjacent 6th district served a single term, while the other 5 House members served 3 consecutive terms (Robert Smith & Orlando Ficklin), 4 terms (John McClernand), and 5 terms (William Richardson -- though he'd serve an additional term later on, in addition to a brief term in the Senate).
Really long House service from that state (longer than 10 years) didn't start until Elihu Washburne, who began his service in 1853 and served 9 consecutive terms until his resignation in 1869. I tended to observe that it wasn't until the latter part of the 19th century when long Congressional service became more usual (although that varied from state to state). It was serving many many terms that allowed Southern Democrats to dominate the Chairmanships of committees in the 20th century, as many Dems from northern states (such as NY) often only served far shorter terms. Following Watergate was when the liberals from these states tossed out a strict seniority system.
The Illinois House members you mention would have had exceptional careers by the standards of their immediate predecessors, and one may offer the languid observation that they probably were indeed the harbingers of the new age of political careerism and professionalism that overthrew and buried the popular political ideals of the Age of Jackson and supplanted them with the rottenness of the Gilded Age.