Will I lose God's favor if I follow both Catholic and Buddhist teachings?

Every religion has its own positives and there are similarities, but you need understand the differences as well.

I am an Indian Christian and was fascinated by the concept of Sanadhana Dharma. Both Buddhism and Hinduism is about a way of rather than a religion. In zen Buddhism has a very attractive philosophy which almost goes in line with Christianity. But there is a major difference, in Buddhism there is no God nor is their the concept of soul.

The fact is you have to choose between these two school of thought. The problem is as Christianity is a monotheistic religion we believe in the Trinity concept of God.

Hence to follow First commandment which says "Thou shalt have no other gods before me" is essential to remain in your Christian faith.

It is ‘either or’ option there is no chance of mixing these and create an option of ‘both’.

The difference between Christian and Buddhism.

Ciril J Thundiyil's answer to Is it right to believe in 'One God'? If yes, why do people fight over religions (since religion is, itself, made by people)?