Tengo dos preguntas

Question

The first question is which verb is used. "to share the gospel" comunicare,decir ,or compartir el evangelio

Second question: does the verb "asegurar take indirect object or direct?

Le aseguro o lo aseguro.

Answer 1

I think several verbs could be used for "to share the gospel" like informar de, or even enseñar depending on exactly what you meant by "share".

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Me gusta referirme a las labores misionales como "compartir el Evangelio". La palabra compartir afirma que tenemos algo extremadamente valioso y deseamos darlo a los demás para su beneficio y bendición.

asegurar

If you look at the dictionary entry above you will see many contexts for asegurar. If you read them, I think you will find your own answer. In general, let me say that asegurar is listed as being able to be used transitively. That means it would have a direct object so a direct object pronoun would have to be possible.

I think the better question would have been: Does asegurar use a reflexive or indirect object pronoun? Look at the examples and see if you can find your own answer. (hint: since it is listed as pronominal it must be able to take a reflexive pronoun). See if you can find an example where an indirect object pronoun is used (transitive or intransitive).