St. Nikon

St. Sergius' successor as monastery abbot was St. Nikon (1355-1426), 1st among his disciples, from Yuriev-Polsky (half way between Rostov and Radonezh). He came to the Trinity Monastery at a very early age, that’s why St. Sergius put him under the guidance of his disciple St. Athanasius, the abbot of the Theotokos on the Mountain monastery in Serpukhov. In 1375 St. Nikon returned to the Trinity Monastery and became St. Sergius' closest coworker. Half a year before his death, St. Sergius entrusted the monastery leadership to St. Nikon and vowed himself to silence. He was monastery abbot until his death. 

St. Nikon rebuilt the entire monastery destroyed during the invasion by Han Edigey in 1408. In 1422 the holy relics of St. Sergius were discovered during the construction of the Trinity Cathedral. St. Nikon commissioned the famous iconographers Andrey Rublev and Daniel the Black to paint the cathedral. The work was finished by 1425. 

St. Nikon was buried by the southern wall of the Trinity Cathedral, where a church dedicated to him was constructed in 1548, a year after his canonization. The church was rebuilt in 1623. At its western wall there is a chapel called Serapion’s Tent, constructed above the tomb of St. Serapion, a Novgorod archbishop.

Holy Spirit Church

In 1476 on the site of the wooden Trinity Church (1412) by St. Nikon, master builders from Pskov invited for the construction work in the Moscow Kremlin erected a new 1-domed church, dedicated to the Descent of the Holy Spirit upon the Apostles. Under the dome the builders placed an open belfry. In 1608–10 during the Polish siege this church was used as a watchtower. 

The Holy Spirit Church and the Trinity Cathedral form an ensemble. The frescoes in the Holy Spirit Church were executed in 1655, but in the middle of the 19th century they were replaced by oil paintings. The iconostasis was carved of rosewood by Lavra woodcarvers in 1866. In the church there are 2 temples with the holy relics of St. Maximus the Greek († 1556) and St. Anthony of Radonezh († 1877). St. Maximus the Greek was one of the most erudite men of his period who wrote many theological and polemic works. He died in the monastery and was buried here. In 1988 he was canonised. Since 1770 Moscow metropolitans were abbots of the monastery. St. Anthony was the monastery vicar in 1831–77 and canonised in 1996.