because they had not met the Israelites with food and water, but had hired Balaam to call down a curse against them (although our God had turned the curse into a blessing).
KJV
Because they met not the children of Israel with bread and with water, but hired Balaam against them, that he should curse them: howbeit our God turned the curse into a blessing.
ASV
because they met not the children of Israel with bread and with water, but hired Balaam against them, to curse them: howbeit our God turned the curse into a blessing.