The older of the two structures, known as Davidskyrkan, is said by tradition to date from around 1055, attributed to the English abbot David, sometimes called the "apostle of Västmanland", who died in 1082. According to legend he baptised converts at a nearby spring, and his remains were kept in a shrine within the church before being transferred to Västerås Cathedral in the 15th century. Munktorp is said to have developed into an ecclesiastical centre for the region as a result.
An alternative explanation holds that Davidskyrkan began life simply as a porch built in front of the main church entrance, rather than as an independent early church. A roof-space inventory found no conclusive evidence to settle the question either way, though the oldest surviving roof timbers are thought to be late medieval, possibly from the 1500s.
The main church grew in stages. It began as a small east-tower church with a short nave and a tower above the chancel. In the 13th century a single-nave hall was added to the west, effectively forming a new church, and in the 1500s side aisles were added, converting the building into a three-aisled basilica some 70 metres long. Some older roof trusses survive, built upon in later periods. The tower itself appears disproportionately large for the original nave and is thought to have been heightened at a later date; it is now topped by a lantern. In 1986 the interior was reoriented for practical reasons, placing the altar of Davidskyrkan to the west.
Inside, visitors can see an unusual ambo formed as an opening within a pillar, used as a reading point during services. Among the furnishings are a bronze font cast in Lübeck around 1360, a 15th-century altar cabinet in the south aisle, a communion vessel dated to the 1400s, and a door between porch and nave from the same century.
The church has had a succession of organs since at least the 17th century, and the present instrument, built in 1944, stands alongside a separate, smaller organ in Davidskyrkan installed in 1970 and later expanded.