R. Yonathan says: Beloved are afflictions. Just as a covenant is forged with the land (viz. Genesis 15:18), a covenant is forged with afflictions, viz. "the L–rd your G–d chastises you … (7) for the L–rd your G–d brings you to a good land."
Rabbi Yonathan Made a Declaration That Would Strike Most People
Mekhilta Tractate Bachodesh 10:9