After his return from Rome, Wołłowicz became more sedentary living mostly in Vilnius and Verkiai. He had long complained of poor health and suffered from grout since at least 1604. He traveled to the Sejm of the Polish–Lithuanian Commonwealth in 1623, 1626, 1627, 1628, but was late to the last three and missed several others. Overall, he attended only half of the 14 Sejms during his tenure as bishop; he missed the Sejms due to his trip to Rome in 1620–1621 and likely due to a plague outbreak in 1624–1625. Around 1618, Wołłowicz and Wawrzyniec Gembicki, Primate of Poland, signed an instruction for diplomatic envoys to Moscow during the Polish–Muscovite War (1605–1618). It was the only time in history that Bishop of Vilnius acted almost like the Primate of Lithuania and an equal to Primate of Poland.