Jäts gamla kyrka

The stone church was built in 1226, a date established by dendrochronological analysis of its surviving roof timbers. It kept its original Romanesque plan of a nave and narrower, straight-ended chancel, separated by a triumphal arch, with walls a metre thick. A porch was added in 1686 and a sacristy, replacing a smaller earlier one, in 1733, both built in horizontal log construction. Traces of the church's original external red decoration survive only in fragments, and the entrance, originally on the south side, was moved to the west in 1796.

By the mid-1800s parishioners considered adding a timber bell tower, but in 1857 they opted instead to build an entirely new parish church nearby. That decision took decades to carry out, and the new Jät church was not completed until 1908–1910. Once it opened, this older building was retired from regular parish use and might have been demolished had the Royal Academy of Letters, History and Antiquities not urged the parish to preserve it instead. Restoration work followed in 1959 and again between 1969 and 1974.

The separate bell tower stands at the south-west corner of the churchyard and probably dates from the 1600s. It was damaged by lightning in 1924, losing its cap and spire to fire, and was rebuilt in 1929 in its present form; a new bell was acquired in 1935 after the originals were transferred to the new church.

Inside, the church is notable for its decorative paintings by the Växjö artist Johan Christian Zschotzscher, completed in 1749. His work covers the nave ceiling with a depiction of the Last Judgement, centred on Christ enthroned on a rainbow, along with acanthus scrollwork and painted drapery around the chancel window; he also decorated both galleries with images of Christ and the apostles. Further paintings in the porch and sacristy, from the 1730s and 1750s, are by other artists of the period and include scenes such as the Trinity, Jacob's dream, and Christ's baptism.

When the font and pulpit were moved to the new church, several older fittings went to the Smålands Museum in Växjö, but some furnishings remain, including a stone altar thought to date from the church's original construction, a late-medieval altar crucifix repainted in the 1600s, box pews probably from the same century, and an oak parish chest with iron fittings. Two memorial plaques commemorate local figures who died in the 1740s and 1770s. The church's small organ, installed in the 1870s by an unrecorded builder, retains its Empire-style case.