There are two kinds of opulence. One, which results from one’s karma, is material, whereas the other is spiritual. A surrendered soul who fully depends upon the Supreme Personality of Godhead does not want material opulence for sense gratification. Therefore when a pure devotee is seen to possess exalted material opulence, it is not due to his karma. Rather, it is due to his bhakti. In other words, he is in that position because the Supreme Lord wants him to execute service to Him very easily and opulently. The special mercy of the Lord for the neophyte devotee is that he becomes materially poor. This is the Lord’s mercy because if a neophyte devotee becomes materially opulent, he forgets the service of the Lord. However, if an advanced devotee is favored by the Lord with opulence, it is not material opulence but a spiritual opportunity. Material opulence offered to the demigods causes forgetfulness of the Lord, but opulence was given to Bali Mahārāja for continuing service to the Lord, which was free from any touch of māyā.
Source: Srimad Bhagavatam 5.24.22 Purport